arm64: dts: mt8183: kukui: Use aliases to mmc nodes

With commit 1796164f ("dt-bindings: mmc: document alias support"),
a way to specify fixed index numbers was provided. This patch use aliases
to mmc nodes so the partition name for eMMC and SD card will be consistent
across boots.

Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20210728040710.2891955-1-hsinyi@chromium.org


Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>