glusterfs.spec.in: resync with Fedora glusterfs.spec

Resync with Fedora's glusterfs.spec, being careful to preserve recent
additions to the glusterfs.spec.in such as the package-config for -devel
and the OCF sub-package

To build a set of RPMs:
 % ./autogen.sh
 % ./configure --enable-fusermount
 % make dist
 % cd extras/LinuxRPM && make glusterrpms

Updated rpm.t, hopefully build system has all the dependencies to build UFO

BUG: 819130
Change-Id: I1b1c161337ad780cf7d3ab401fa1b10648f38cbd
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>
Reviewed-on: http://review.gluster.org/4454
Reviewed-by: Peter Portante <pportant@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>