Use "mcs" as policy name instead of "clip".

One policy was called "clip" and the other "mls",
more accurately one is actually "mcs" and the other
"mls".  Both are CLIP policies, but use the type
to differentiate.

This also generate per-type individual
policy RPMs when necessary, e.g.
clip-selinux-policy-mcs-aide
clip-selinux-policy-mls-aide