soc: rockchip: ROCKCHIP_GRF should not default to y, unconditionally

Merely enabling CONFIG_COMPILE_TEST should not enable additional code.
To fix this, restrict the automatic enabling of ROCKCHIP_GRF to
ARCH_ROCKCHIP, and ask the user in case of compile-testing.

Fixes: 4c58063d ("soc: rockchip: add driver handling grf setup")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20210208143855.418374-1-geert+renesas@glider.beSigned-off-by: NHeiko Stuebner <heiko@sntech.de>

drivers/soc/rockchip/Kconfig

@@ -6,8 +6,8 @@ if ARCH_ROCKCHIP || COMPILE_TEST
 #
 
 config ROCKCHIP_GRF
-	bool
-	default y
+	bool "Rockchip General Register Files support" if COMPILE_TEST
+	default y if ARCH_ROCKCHIP
 	help
 	  The General Register Files are a central component providing
 	  special additional settings registers for a lot of soc-components.