arm64: defconfig: add S32G RTC module support

The RTC hardware module present on S32G based SoCs tracks clock time
during system suspend and it is used as a wakeup source on S32G2/S32G3
architecture.

Signed-off-by: Ciprian Marian Costea <ciprianmarian.costea@oss.nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>