davinci: DMx and da8xx defconfig updates

DMx:
- enable MMC and dm365evm_keys
- Enable DM355 and DM365 input drivers as modules.

da8xx
- combine da830 and da850 into common defconfig
- drop SYSFS_DEPRECATED flag
- auto-select D$ writethrough for da830
- enable CPUfreq and FB

Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>