[media] au0828: remove CONFIG_VIDEO_AU0828_RC scope around au0828_rc_*()

Remove CONFIG_VIDEO_AU0828_RC scope around au0828_rc_register()
and au0828_rc_unregister() calls in au0828-core

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>