Add in the AR9285 (Kite) diversity to if_ath, enabling TX/RX antenna

diversity.

This is bit dirty and likely should be revised at a later date,
with an eye to unifying/tidying up the whole diversity setup
and allowing developers to do "tricky stuff" as they desire.
For now, this works.

sys/dev/ath/if_ath.c

@@ -3615,6 +3615,12 @@ ath_rx_proc(void *arg, int npending)
 			} else
 				sc->sc_rxotherant = 0;
 		}
+
+		/* Newer school diversity - kite specific for now */
+		/* XXX perhaps migrate the normal diversity code to this? */
+		if ((ah)->ah_rxAntCombDiversity)
+			(*(ah)->ah_rxAntCombDiversity)(ah, rs, ticks, hz);
+
 		if (sc->sc_softled) {
 			/*
 			 * Blink for any data frame.  Otherwise do a