brcm80211: smac: fix endianess issue for OTP memory access

This fixes issue when using OTP memory. It was introduced by
following commit:

commit 028f78d4
Author: Arend van Spriel <arend@broadcom.com>
Date:   Fri Oct 21 16:16:35 2011 +0200

    brcm80211: smac: change buffer endianess convert function interface

Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>