RDMA/nes: Resurrect error path dead code

RDMA/nes: Resurrect error path dead code

Adrian Bunk pointed out that a Coverity scan found some apparently
dead code in nes_verbs.c that really shouldn't have been dead.

The function nes_create_cq() was missing the assignment

	err = 1;

just prior to an iteration that conditionally set err = 0 if a PBL was
found for a given virtual CQ.  I also noticed we should have been
returning -EFAULT on a couple related error paths.

Signed-off-by: Chien Tung <ctung@neteffect.com>
Signed-off-by: Glenn Streiff <gstreiff@neteffect.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>