IB/mlx5: Fix entries check in mlx5_ib_resize_cq

Verify that number of entries is less than device capability.
Add an appropriate warning message for error flow.

Fixes: bde51583

 ('IB/mlx5: Add support for resize CQ')
Signed-off-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>