clocksource/drivers/exynosy: Depend on sub-architecture for Exynos MCT and Samsung PWM

The Exynos MCT and Samsung PWM Timer clocksource drivers are not usable
on anything else than Samsung Exynos, S3C or S5P SoC platforms.  These
are integral parts of a SoC.  Even though the drivers are not user
selectable, still document the hardware architecture explicitly with
depends on ARCH_EXYNOS and others.  This also serves a purpose of
documenting use-case, if someone ever wonders whether to select the
driver for his platform.  No functional change, because drivers are
already selected by the platform described in depends. We follow similar
approach also for other SoC-specific drivers.

Signed-off-by: Krzysztof Kozlowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Daniel Lezcano <[email protected]>

Author: krzk

drivers/clocksource/Kconfig

@@ -417,12 +417,14 @@ config ATMEL_TCB_CLKSRC
 config CLKSRC_EXYNOS_MCT
 	bool "Exynos multi core timer driver" if COMPILE_TEST
 	depends on ARM || ARM64
+	depends on ARCH_EXYNOS || COMPILE_TEST
 	help
 	  Support for Multi Core Timer controller on Exynos SoCs.
 
 config CLKSRC_SAMSUNG_PWM
 	bool "PWM timer driver for Samsung S3C, S5P" if COMPILE_TEST
 	depends on HAS_IOMEM
+	depends on ARCH_EXYNOS || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210 || COMPILE_TEST
 	help
 	  This is a new clocksource driver for the PWM timer found in
 	  Samsung S3C, S5P and Exynos SoCs, replacing an earlier driver