staging: brcm80211: remove usage of struct osl_info for register access

Register access to the device uses a flag in struct osl_info to determine
whether to use memory mapped access or not. This check was not needed as
it boils down to memory mapped for brcmsmac driver and not for brcmfmac
driver. Only use of struct osl_info is reduced to keeping track of the
number of allocated sk_buffs within the driver(s).

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