ath5k: Fix bitmasks and typos for PCU Diagnostic register

As reported by Ryan Niemi, some bitmasks in the register definition for the PCU
Diagnostic register (DIAG_SW) were missing a zero at the end. While at it fix
some typos and add more comments.

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath5k/phy.c b/drivers/net/wireless/ath/ath5k/phy.c
index 4932bf2..61da913 100644
--- a/drivers/net/wireless/ath/ath5k/phy.c
+++ b/drivers/net/wireless/ath/ath5k/phy.c
@@ -1257,7 +1257,7 @@
 	 * Disable beacons and RX/TX queues, wait
 	 */
 	AR5K_REG_ENABLE_BITS(ah, AR5K_DIAG_SW_5210,
-		AR5K_DIAG_SW_DIS_TX | AR5K_DIAG_SW_DIS_RX_5210);
+		AR5K_DIAG_SW_DIS_TX_5210 | AR5K_DIAG_SW_DIS_RX_5210);
 	beacon = ath5k_hw_reg_read(ah, AR5K_BEACON_5210);
 	ath5k_hw_reg_write(ah, beacon & ~AR5K_BEACON_ENABLE, AR5K_BEACON_5210);
 
@@ -1336,7 +1336,7 @@
 	 * Re-enable RX/TX and beacons
 	 */
 	AR5K_REG_DISABLE_BITS(ah, AR5K_DIAG_SW_5210,
-		AR5K_DIAG_SW_DIS_TX | AR5K_DIAG_SW_DIS_RX_5210);
+		AR5K_DIAG_SW_DIS_TX_5210 | AR5K_DIAG_SW_DIS_RX_5210);
 	ath5k_hw_reg_write(ah, beacon, AR5K_BEACON_5210);
 
 	return 0;