net: atlantic: fix variable type in aq_ethtool_get_pauseparam

This patch fixes the type for variable which is assigned from enum,
as such it should have been int, not u32.

Signed-off-by: Nikita Danilov <ndanilov@marvell.com>
Signed-off-by: Mark Starovoytov <mstarovoitov@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>