RDMA: remove useless condition in siw_create_cq()

Comparison of 'cq' with NULL is useless since
'cq' is a result of container_of and cannot be NULL
in any reasonable scenario.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 303ae1cd ("rdma/siw: application interface")
Link: https://lore.kernel.org/r/20220711151251.17089-1-strochuk@ispras.ruSigned-off-by: Andrey Strachuk <strochuk@ispras.ru>
Acked-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

drivers/infiniband/sw/siw/siw_verbs.c

@@ -1167,7 +1167,7 @@ int siw_create_cq(struct ib_cq *base_cq, const struct ib_cq_init_attr *attr,
 err_out:
 	siw_dbg(base_cq->device, "CQ creation failed: %d", rv);
 
-	if (cq && cq->queue) {
+	if (cq->queue) {
 		struct siw_ucontext *ctx =
 			rdma_udata_to_drv_context(udata, struct siw_ucontext,
 						  base_ucontext);