rt3883.mk contains both RT3662 and RT3883 device profiles, but commit
6a104ac772 set MTK_SOC to rt3883 for all devices. This patch fixes it,
and renames dts files accordingly. And SoC compatible strings are also
appended in the dts.
Fixes: 6a104ac772 ("ramips/rt288x,rt3883: Name DTS files based on scheme")
Signed-off-by: Sungbo Eo <mans0n@gorani.run>
