rpms: Fix handling of x86 architectures

rpms: Fix handling of x86 architectures

Once upon a time, our specfile would assume that if you were
building for i386 you were building userspace, and that i586 or i686
implied doing a kernel only build. This is no longer the case, and
now everything on modern Fedora is built for i686, so we should adapt
the spec file for this.

Change-Id: Ia56b9b15d0b28672a8411417d38937ed45ee93a1
Reviewed-on: http://gerrit.openafs.org/4970
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>