RDMA/ocrdma: Fix error codes in ocrdma_create_srq()

If either of these allocations fail then we return ERR_PTR(0).  That's
equivalent to NULL and results in a NULL pointer dereference in the
caller.

Fixes: fe2caefc ("RDMA/ocrdma: Add driver for Emulex OneConnect IBoE RDMA adapter")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>