Rather than requiring platforms to select the generic clock API to make
it available make the API available as a user selectable option unless the
user either selects HAVE_CUSTOM_CLK (if they have their own implementation)
or selects COMMON_CLK (if they depend on the generic implementation).
All current architectures that HAVE_CLK but don't use the common clock
framework have selects of HAVE_CUSTOM_CLK added.
This allows drivers to use the generic API on platforms which have no need
for the clock API at platform level.
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
@@ -674,6 +676,7 @@ config ARCH_TEGRA
select GENERIC_CLOCKEVENTS
select GENERIC_GPIO
select HAVE_CLK
+ select HAVE_CUSTOM_CLK