staging: rtl8723au: Reference correct firmwarefiles with MODULE_FIRMWARE()

Add missing firmware references, and request the correct one.

Reported-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>