ath9k_hw: remove ATH9K_CAP_TKIP_SPLIT

This is only used as a workaround for an issue in one specific hw revision.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index f66b357..4bdf8c8 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -385,7 +385,7 @@
 	 * With split mic keys the number of stations is limited
 	 * to 27 otherwise 59.
 	 */
-	if (ath9k_hw_getcapability(sc->sc_ah, ATH9K_CAP_TKIP_SPLIT, 0, NULL))
+	if (!(sc->sc_ah->misc_mode & AR_PCU_MIC_NEW_LOC_ENA))
 		common->splitmic = 1;
 
 	/* turn on mcast key search if possible */