cluster/afr: UNWIND if opendir returns an error.
cluster/afr: UNWIND if opendir returns an error.

Signed-off-by: Vijay Bellur <vijay@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 756 (simaltaneous rm -rf hangs the clients)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=756

Kaushikbv/Gluster,Kaushikbv/Gluster,Kaushikbv/Gluster