ath9k: Make ath_chanctx_work static

Also compile it conditionally based on
CONFIG_ATH9K_CHANNEL_CONTEXT.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/ath9k.h

@@ -633,7 +633,6 @@ void ath9k_csa_update(struct ath_softc *sc);
 #define ATH_PAPRD_TIMEOUT         100 /* msecs */
 #define ATH_PLL_WORK_INTERVAL     100
 
-void ath_chanctx_work(struct work_struct *work);
 void ath_tx_complete_poll_work(struct work_struct *work);
 void ath_reset_work(struct work_struct *work);
 bool ath_hw_check(struct ath_softc *sc);

drivers/net/wireless/ath/ath9k/channel.c

@@ -305,15 +305,6 @@ static void ath_chanctx_set_next(struct ath_softc *sc, bool force)
 	ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_SWITCH);
 }
 
-void ath_chanctx_work(struct work_struct *work)
-{
-	struct ath_softc *sc = container_of(work, struct ath_softc,
-					    chanctx_work);
-	mutex_lock(&sc->mutex);
-	ath_chanctx_set_next(sc, false);
-	mutex_unlock(&sc->mutex);
-}
-
 void ath_chanctx_init(struct ath_softc *sc)
 {
 	struct ath_chanctx *ctx;
@@ -949,6 +940,15 @@ static void ath_offchannel_timer(unsigned long data)
 	}
 }
 
+static void ath_chanctx_work(struct work_struct *work)
+{
+	struct ath_softc *sc = container_of(work, struct ath_softc,
+					    chanctx_work);
+	mutex_lock(&sc->mutex);
+	ath_chanctx_set_next(sc, false);
+	mutex_unlock(&sc->mutex);
+}
+
 void ath9k_init_channel_context(struct ath_softc *sc)
 {
 	INIT_WORK(&sc->chanctx_work, ath_chanctx_work);