staging: brcm80211: remove volatile keyword used in struct rte_console

Two members vcons_in and vcons_out were declared using the volatile
keyword. However, there is no reason for doing so. The member is
used only to calculate the backplane address to access using offsetof.
This address is passed to subsequent read function. Use of volatile
is not warranted.

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