libglusterfs/syncop: implement inodelk

Change-Id: Iea489157490b70cb2bb03576b0d4943c6d8f052d
BUG: 1140348
Signed-off-by: Raghavendra G <rgowdapp@redhat.com>
Reviewed-on: http://review.gluster.org/8522
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
(cherry picked from commit 172100209e531e94168d0974bfb0995704d9dddd)
Signed-off-by: Nithya Balachandran <nbalacha@redhat.com>
Reviewed-on: http://review.gluster.org/8723
Reviewed-by: Shyamsundar Ranganathan <srangana@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>