qed: Correct Multicast API to reflect existence of 256 approximate buckets.

FW hsi contains 256 approximation buckets which are split in ramrod into
eight u32 values, but driver is using eight 'unsigned long' variables.

This patch fixes the mcast logic by making the API utilize u32.

Fixes: 83aeb933 ("qed*: Trivial modifications")
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>