rt2x00: Rename CONFIG_DISABLE_LINK_TUNING

Rename CONFIG_DISABLE_LINK_TUNING to DRIVER_SUPPORT_LINK_TUNING
Link tuning support is not only based on EEPROM decisions, but
also if the device actually supports it.

Currently only rt2500usb doesn't support link tuning because
of hardware problems. But rt2800usb is also suspected of having
problems with link tuning.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2x00link.c b/drivers/net/wireless/rt2x00/rt2x00link.c
index 2f8136c..801925b 100644
--- a/drivers/net/wireless/rt2x00/rt2x00link.c
+++ b/drivers/net/wireless/rt2x00/rt2x00link.c
@@ -359,10 +359,11 @@
 		qual->rssi = link->avg_rssi.avg;
 
 	/*
-	 * Only perform the link tuning when Link tuning
-	 * has been enabled (This could have been disabled from the EEPROM).
+	 * Check if link tuning is supported by the hardware, some hardware
+	 * do not support link tuning at all, while other devices can disable
+	 * the feature from the EEPROM.
 	 */
-	if (!test_bit(CONFIG_DISABLE_LINK_TUNING, &rt2x00dev->flags))
+	if (test_bit(DRIVER_SUPPORT_LINK_TUNING, &rt2x00dev->flags))
 		rt2x00dev->ops->lib->link_tuner(rt2x00dev, qual, link->count);
 
 	/*