RDMA/rxe: Remove unused qp parameter

The qp parameter in free_rd_atomic_resource() has become
unused so remove it directly.

Fixes: 15ae1375

 ("RDMA/rxe: Fix qp reference counting for atomic ops")
Link: https://lore.kernel.org/all/20220708035547.6592-1-yangx.jy@fujitsu.com/
Signed-off-by: Xiao Yang <yangx.jy@fujitsu.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>