KVM: VMX: rename RDSEED and RDRAND vmx ctrls to reflect exiting

Let's just name these according to the SDM. This should make it clearer
that the are used to enable exiting and not the feature itself.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>