ath5k: use AR5K_KEYTABLE_SIZE when initializing key table

...instead of using AR5K_KEYCACHE_SIZE, which would seem to be a
typo/thinko...
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath5k/base.c

@@ -663,7 +663,7 @@ ath5k_attach(struct pci_dev *pdev, struct ieee80211_hw *hw)
 	 * Reset the key cache since some parts do not
 	 * reset the contents on initial power up.
 	 */
-	for (i = 0; i < AR5K_KEYCACHE_SIZE; i++)
+	for (i = 0; i < AR5K_KEYTABLE_SIZE; i++)
 		ath5k_hw_reset_key(ah, i);
 
 	/*