RedHat: Munge future kernel versions

We currently look for "fc1?" (that is, fc10 through fc19) when trying
to munge the kernel version in some ways. This broke on Fedora 20,
since 20 obviously does not match "fc1?". Similarly, we look
specifically for "el6" for RHEL6 versioning quirks, but these will
break on RHEL7 and beyond.

Change the version checks so that this will work all the way through
Fedora 99 and RHEL 9. That won't work forever, but it will keep us
working for a few versions if the versioning quirks do not change.

Change-Id: I64dfd483eb2cfa57d67c97ae6db09be5bb020195
Reviewed-on: http://gerrit.openafs.org/10618
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Reviewed-by: Ken Dreyer <ktdreyer@ktdreyer.com>