ath9k: disable RNG by default

ath9k RNG will dominates all the noise sources from the real HW
RNG, disable it by default. But we strongly recommand to enable
it if the system without HW RNG, especially on embedded systems.

Signed-off-by: Miaoqing Pan <miaoqing@codeaurora.org>
Acked-by: Stephan Mueller <smueller@chronox.de>
Acked-by: Stephan Mueller <smueller@chronox.de>
Reviewed-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath9k/Kconfig

@@ -180,7 +180,7 @@ config ATH9K_HTC_DEBUGFS
 config ATH9K_HWRNG
 	bool "Random number generator support"
 	depends on ATH9K && (HW_RANDOM = y || HW_RANDOM = ATH9K)
-	default y
+	default n
 	---help---
 	  This option incorporates the ADC register output as a source of
 	  randomness into Linux entropy pool (/dev/urandom and /dev/random)