aarch64: add support for rtc hwclock

Add support for UEFI RTC hardware clock. Without this change, the docker
images cannot be pulled because hwclock does not have any clock source
on KVM.

Signed-off-by: Adrian Vladu <avladu@cloudbasesolutions.com>

Author: ader1990

kernel/config-5.10.x-aarch64

@@ -4578,7 +4578,7 @@ CONFIG_RTC_I2C_AND_SPI=y
 # CONFIG_RTC_DRV_DS1685_FAMILY is not set
 # CONFIG_RTC_DRV_DS1742 is not set
 # CONFIG_RTC_DRV_DS2404 is not set
-# CONFIG_RTC_DRV_EFI is not set
+CONFIG_RTC_DRV_EFI=y
 # CONFIG_RTC_DRV_STK17TA8 is not set
 # CONFIG_RTC_DRV_M48T86 is not set
 # CONFIG_RTC_DRV_M48T35 is not set