staging: brcm80211: fix #ifdef BRCM_FULLMAC mess

This patch fixes "#ifdef BRCM_FULLMAC" mess which shows
in siutils.c/hndpmu.c.
All unnecessary #ifdefs were erased.
Also as a part of this work, bcmutils.c was also modified.

Signed-off-by: Nohee Ko <noheek@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>