x86/Kconfig: Remove HPET_EMULATE_RTC depends on RTC

The RTC config option was removed in commit f52ef24b ("rtc/alpha:
remove legacy rtc driver")
Signed-off-by: Anand K Mistry <amistry@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210204183205.1.If5c6ded53a00ecad6a02a1e974316291cc0239d1@changeid

arch/x86/Kconfig

@@ -889,7 +889,7 @@ config HPET_TIMER
 
 config HPET_EMULATE_RTC
 	def_bool y
-	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
+	depends on HPET_TIMER && (RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 
 config APB_TIMER
 	def_bool y if X86_INTEL_MID