This code is trying to ensure that only the flags specified in the list
are allowed.  The problem is that ucmd->rx_hash_fields_mask is a u64 and
the flags are an enum which is treated as a u32 in this context.  That
means the test doesn't check whether the highest 32 bits are zero.

Fixes: 4d02ebd9 ("IB/mlx4: Fix RSS hash fields restrictions")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/233ed975-982d-422a-b498-410f71d8a101@moroto.mountainSigned-off-by: Leon Romanovsky <leon@kernel.org>