arm64: dts: exynos: add mmc aliases

Add aliases for eMMC and SD card where applicable, so that
assigned mmc indeces are always the same.

Signed-off-by: Henrik Grimler <henrik@grimler.se>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20230315212814.15908-3-henrik@grimler.se


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>