s390: Remove protvirt and kvm config guards for uv code

Removing the CONFIG_PROTECTED_VIRTUALIZATION_GUEST ifdefs and config
option as well as CONFIG_KVM ifdefs in uv files.

Having this configurable has been more of a pain than a help.
It's time to remove the ifdefs and the config option.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>