staging: brcm80211: remove unused sdioh command type code in fullmac

sdioh command type is not used in brcmf_sdioh_request_word. This patch
removes the related code.

Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Reviewed-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>