Previously, the mshc0 alias has been necessary so that
MMC_CAP_1_8V_DDR | MMC_CAP_8_BIT_DATA are set for mshc_0/mmc_0.
However, these capabilities should be described in the device tree so
that we do not have to rely on the alias.

The property mmc-ddr-1_8v replaces MMC_CAP_1_8V_DDR, while bus_width =
<8>, which is already set for all the mshc0/mmc0 nodes, replaces
MMC_CAP_8_BIT_DATA.

Also drop other mshc aliases as they are not needed.
Signed-off-by: Henrik Grimler <henrik@grimler.se>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20230402144724.17839-2-henrik@grimler.seSigned-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>