ath5k: Add proper dependency for ATH5K_AHB

The CONFIG_ATH5K_AHB could be enabled on ATH25 system without enabling
ATH5K driver itself.  This does not make sense because CONFIG_ATH5K_AHB
controls object build within drivers/net/wireless/ath/ath5k/ so enabling
it without CONFIG_ATH5K brings nothing.

Add proper dependency to CONFIG_ATH5K_AHB.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/ath5k/Kconfig

@@ -54,7 +54,7 @@ config ATH5K_TRACER
 
 config ATH5K_AHB
 	bool "Atheros 5xxx AHB bus support"
-	depends on ATH25
+	depends on ATH25 && ATH5K
 	---help---
 	  This adds support for WiSoC type chipsets of the 5xxx Atheros
 	  family.