arm64: dts: allwinner: h5: libretech-all-h3-cc: Mark eMMC HS-DDR 3.3V capable

The Libre Computer ALL-H3-CC H5 is one of the few boards that can have
its eMMC run at HS-DDR speed mode. Mark it as such.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>