I have a host which was updated since 3.6....
libcacard is disappeared from ovirt4.1 but it has a many dependencies which stops to remove it:

[root@clei36 ~]# yum list installed | grep ovirt| grep 4.0
libcacard-ev.x86_64                    10:2.3.0-31.el7.16.1           @ovirt-4.0

yum update libcacard-ev
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: ftp.fau.de
 * epel: ftp.fau.de
 * extras: ftp.fau.de
 * ovirt-4.1: ftp.nluug.nl
 * ovirt-4.1-epel: ftp.fau.de
 * updates: mirror.eu.oneandone.net
No packages marked for update

yum remove  libcacard-ev.x86_64
Loaded plugins: fastestmirror
Resolving Dependencies
--> Running transaction check
---> Package libcacard-ev.x86_64 10:2.3.0-31.el7.16.1 will be erased
--> Processing Dependency: libcacard.so.0()(64bit) for package: 10:qemu-kvm-ev-2.6.0-28.el7_3.3.1.x86_64
--> Running transaction check
---> Package qemu-kvm-ev.x86_64 10:2.6.0-28.el7_3.3.1 will be erased
--> Processing Dependency: qemu-kvm >= 1.5.3-92.el7 for package: 1:virt-v2v-1.32.7-3.el7.centos.2.x86_64
--> Processing Dependency: qemu-kvm for package: libvirt-daemon-kvm-2.0.0-10.el7_3.4.x86_64
--> Processing Dependency: qemu-kvm-rhev >= 10:2.6.0-2 for package: vdsm-4.19.4-1.el7.centos.x86_64
--> Running transaction check
---> Package libvirt-daemon-kvm.x86_64 0:2.0.0-10.el7_3.4 will be erased
--> Processing Dependency: libvirt-daemon-kvm >= 1.2.8-3 for package: 1:libguestfs-1.32.7-3.el7.centos.2.x86_64
---> Package vdsm.x86_64 0:4.19.4-1.el7.centos will be erased
--> Processing Dependency: vdsm = 4.19.4-1.el7.centos for package: vdsm-hook-vmfex-dev-4.19.4-1.el7.centos.noarch
---> Package virt-v2v.x86_64 1:1.32.7-3.el7.centos.2 will be erased
--> Processing Dependency: virt-v2v for package: safelease-1.0-7.el7.x86_64
--> Running transaction check
---> Package libguestfs.x86_64 1:1.32.7-3.el7.centos.2 will be erased
--> Processing Dependency: libguestfs = 1:1.32.7-3.el7.centos.2 for package: 1:libguestfs-tools-c-1.32.7-3.el7.centos.2.x86_64
--> Processing Dependency: libguestfs >= 1:1.28.1 for package: libguestfs-winsupport-7.2-1.el7.x86_64
--> Processing Dependency: libguestfs.so.0()(64bit) for package: 1:libguestfs-tools-c-1.32.7-3.el7.centos.2.x86_64
---> Package safelease.x86_64 0:1.0-7.el7 will be erased
---> Package vdsm-hook-vmfex-dev.noarch 0:4.19.4-1.el7.centos will be erased
--> Running transaction check
---> Package libguestfs-tools-c.x86_64 1:1.32.7-3.el7.centos.2 will be erased
---> Package libguestfs-winsupport.x86_64 0:7.2-1.el7 will be erased
--> Finished Dependency Resolution

Dependencies Resolved

==============================================================================================================================================================================================================================
 Package                                                 Arch                                     Version                                                   Repository                                                   Size
==============================================================================================================================================================================================================================
Removing:
 libcacard-ev                                            x86_64                                   10:2.3.0-31.el7.16.1                                      @ovirt-4.0                                                   47 k
Removing for dependencies:
 libguestfs                                              x86_64                                   1:1.32.7-3.el7.centos.2                                   @updates                                                    3.8 M
 libguestfs-tools-c                                      x86_64                                   1:1.32.7-3.el7.centos.2                                   @updates                                                     14 M
 libguestfs-winsupport                                   x86_64                                   7.2-1.el7                                                 @base                                                       2.2 M
 libvirt-daemon-kvm                                      x86_64                                   2.0.0-10.el7_3.4                                          @updates                                                    0.0 
 qemu-kvm-ev                                             x86_64                                   10:2.6.0-28.el7_3.3.1                                     @ovirt-4.1                                                  9.6 M
 safelease                                               x86_64                                   1.0-7.el7                                                 @centos-ovirt41-candidate                                    43 k
 vdsm                                                    x86_64                                   4.19.4-1.el7.centos                                       @ovirt-4.1                                                  2.5 M
 vdsm-hook-vmfex-dev                                     noarch                                   4.19.4-1.el7.centos                                       @ovirt-4.1                                                   21 k
 virt-v2v                                                x86_64                                   1:1.32.7-3.el7.centos.2                                   @updates                                                     16 M

Transaction Summary
==============================================================================================================================================================================================================================
Remove  1 Package (+9 Dependent packages)

Installed size: 49 M
Is this ok [y/N]: n