ARM: samsung: don't build plat/pm-common for Exynos

This file has not had any callers since linux-4.7, so
stop building it.

Fixes: 5901f4c2 ("ARM: EXYNOS: Remove SROM related register settings from mach-exynos")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20200806182059.2431-10-krzk@kernel.orgSigned-off-by: Krzysztof Kozlowski <krzk@kernel.org>

arch/arm/plat-samsung/Makefile

@@ -25,7 +25,6 @@ obj-$(CONFIG_GPIO_SAMSUNG)     += gpio-samsung.o
 # PM support
 
 obj-$(CONFIG_PM_SLEEP)		+= pm-common.o
-obj-$(CONFIG_EXYNOS_CPU_SUSPEND) += pm-common.o
 obj-$(CONFIG_SAMSUNG_PM)	+= pm.o
 obj-$(CONFIG_SAMSUNG_PM_GPIO)	+= pm-gpio.o
 obj-$(CONFIG_SAMSUNG_PM_CHECK)	+= pm-check.o