GFS2: change gfs2_quota_scan into a shrinker

Deallocation of gfs2_quota_data objects now happens on-demand through a
shrinker instead of routinely deallocating through the quotad daemon.

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

diff --cc fs/gfs2/incore.h
Simple merge

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

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

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

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

diff --cc fs/gfs2/quota.h
Simple merge

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