clk: make CONFIG_COMMON_CLK invisible

All platforms that use the common clk infrastructure should select
COMMON_CLK from platform code, and on all other platforms, it must
not be enabled, so there is no point making the option visible to
users, and when it is visible, we break randconfig builds.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

drivers/clk/Kconfig

@@ -9,21 +9,18 @@ config HAVE_CLK_PREPARE
 config HAVE_MACH_CLKDEV
 	bool
 
-menuconfig COMMON_CLK
-	bool "Common Clock Framework"
+config COMMON_CLK
+	bool
 	select HAVE_CLK_PREPARE
 	---help---
 	  The common clock framework is a single definition of struct
 	  clk, useful across many platforms, as well as an
 	  implementation of the clock API in include/linux/clk.h.
 	  Architectures utilizing the common struct clk should select
-	  this automatically, but it may be necessary to manually select
-	  this option for loadable modules requiring the common clock
-	  framework.
-
-	  If in doubt, say "N".
+	  this option.
 
-if COMMON_CLK
+menu "Common Clock Framework"
+	depends on COMMON_CLK
 
 config COMMON_CLK_DISABLE_UNUSED
 	bool "Disabled unused clocks at boot"
@@ -47,4 +44,4 @@ config COMMON_CLK_DEBUG
 	  clk_flags, clk_prepare_count, clk_enable_count &
 	  clk_notifier_count.
 
-endif
+endmenu