arm: dts: imx8qm-mek: fix boot

serial_init runs into panic because no serial device found.
Update the device tree to include bootph-some-ram for some critial
devices needed in pre-reloc stage

Also update usdhc related properties to avoid card initialization
failure.

Fixes: 8c103c33fb1 ("dm: dts: Convert driver model tags to use new schema")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
2 files changed