ARM: shmobile: Enable NXP pcf85363 rtc in shmobile_defconfig

The iWave RZ/G1C SBC supports RTC (NXP pcf85263). To increase hardware
support enable the driver in the shmobile_defconfig multiplatform
configuration.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>