GFS2: Fix type mapping for demote_rq interface

Mostly the glock operations follow the type of the glock. The
one exception is the transaction glock, so we need to check for
that directly.

Reported-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --cc fs/gfs2/glops.c
Simple merge

diff --cc fs/gfs2/sys.c
Simple merge