Do not look for 'RELEASE*' (including RELEASE-pNN) when evaluating
if checksum files should be included.

This case was specifically added to handle a case where a final
release was a re-roll, i.e., 11.0-RELEASE was really 11.0-RELEASE-p1;
this will need to be handled on a case-by-case basis.

There be dragons. Here lies Link.

Reported by: David Boyd
Sponsored by: The FreeBSD Foundation