socket: unix socket connect path can't be greater than UNIX_PATH_MAX characters

Change-Id: I74788b63dd1c14507aa6d65182ea4b87a2e1f389
BUG: 1046308
Signed-off-by: Krishnan Parthasarathi <kparthas@redhat.com>
Reviewed-on: http://review.gluster.org/6589
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijaikumar Mallikarjuna <vmallika@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>