tests/afr: gfid mismatch test

Change-Id: I12bae9c4035d5b28292e8085a5b600a3e22abaf4
BUG: 1080759
Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Reviewed-on: http://review.gluster.org/7342
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>