mediatek: unify Kconfig with other vendors

Part of reorganising wireless drivers directory and Kconfig.

Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/mediatek/Kconfig

@@ -1,10 +1,14 @@
-menuconfig WL_MEDIATEK
-	bool "Mediatek Wireless LAN support"
+config WLAN_VENDOR_MEDIATEK
+	bool "MediaTek devices"
+	default y
 	---help---
-	  Enable community drivers for MediaTek WiFi devices.
-	  Those drivers make use of the Linux mac80211 stack.
+	  If you have a wireless card belonging to this class, say Y.
 
+	  Note that the answer to this question doesn't directly affect the
+	  kernel: saying N will just cause the configurator to skip all
+	  the questions about  cards. If you say Y, you will be asked for
+	  your specific card in the following questions.
 
-if WL_MEDIATEK
+if WLAN_VENDOR_MEDIATEK
 source "drivers/net/wireless/mediatek/mt7601u/Kconfig"
-endif # WL_MEDIATEK
+endif # WLAN_VENDOR_MEDIATEK