staging: brcm80211: Convert ETHER_IS<FOO> to is_<foo>_ether_addr

Use the normal kernel calls and remove the #defines
for ETHER_IS_BCAST and ETHER_IS_NULLADDR.

Add #include for etherdevice.h where necessary.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>