RDMA/mlx4: Fix create qp command alignment

Avoid extra padding by replacing the order of inl_recv_sz and reserved,
otherwise 'mlx4_ib_create_qp' structure might be larger than legacy user
input leading to copy of some garbage data from the user space buffer.

Fixes: ea30b966 ('IB/mlx4: Add inline-receive support')
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>