mac80211: fix alignment issue with compare_ether_addr()

This addresses an alignment issue with compare_ether_addr().
The addresses passed to compare_ether_addr should be two bytes aligned.
It may function properly in x86 platform. However may not work properly
on IA-64 or ARM processor.

This also fixes a typo in mlme.c where the sk_buff struct name is incorect.
Though sizeof() works for any incorrect structure pointer name as its just
a pointer length that we want, lets just fix it.

Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>