net: pch_gbe: Inline pch_gbe_mac_mc_addr_list_update

The pch_gbe driver sets up multicast address filters using a convoluted
mechanism by which pch_gbe_set_multi allocates an array to hold
multicast addresses, copies desired addresses into that array, calls a
pch_gbe_mac_mc_addr_list_update function which copies addresses out of
that array into MAC registers, then frees the array.

This patch simplifies this somewhat by inlining
pch_gbe_mac_mc_addr_list_update into pch_gbe_set_multi, and removing the
requirement for the MAC addresses to stored consecutively in a single
array.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: David S. Miller <davem@davemloft.net>