cluster/afr: send opendirs to all children for entry self-heal

Problem: In entry self-heal, opendir was sent only to one source because of
which afr_sh_erase_pending() failed to clear the changelogs of other sources. So
heals were happening multiple times.

Fix :Send opendir to all sources.

Change-Id: Ief4f131848b24a0da782f29b9f1d40e136d3fcff
BUG: 1096040
Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Reviewed-on: http://review.gluster.org/7723
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>