[GFS2] System won't suspend with GFS2 file system mounted

The kernel threads in gfs2, namely gfs2_scand, gfs2_logd, gfs2_quotad,
gfs2_glockd, gfs2_recoverd weren't doing anything when the suspend
mechanism was trying to freeze them.

I put in calls to refrigerator() in the loops for all the daemons and
suspend works as expected.

Signed-off-by: Abhijith Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>