staging: rtl8723au: rates are always set via the firmware interface

The only case where fw_ractrl = false was when the firmware failed to
load, and in that case we are dead in the water anyway.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>