I've asked the epel7 branch of libvncserver which is missing in ppc as per packaging policy guidelines:

https://fedoraproject.org/wiki/EPEL:Packaging#Limited_Arch_Packages

I will be adding the same epel7 package with a prefixed 0 in the release field.

SCM request:

https://bugzilla.redhat.com/show_bug.cgi?id=429749

Regards, --Simone