1165355 - Add a sanitize_checksum_type function.

https://bugzilla.redhat.com/show_bug.cgi?id=1165355
Merge branch '2.4-testing' into 2.4-dev
Merge branch '2.4-dev' into 2.5-testing
Merge branch '2.5-testing' into 2.6-dev
Merge branch '2.6-dev'