Staging: rt3070: remove dead CONFIG_AP_SUPPORT code

Then remove no longer needed IF_DEV_CONFIG_OPMODE_ON_[AP,STA]() macros.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>