Revert "ascend-g300: change to b2g device branch"

This reverts commit f9b727c19852224ce333abeed8097af1ba862ea8.
Revert "ascend-g300: use my platform_build"

This reverts commit fb1c5de7c12c0c34025d14ac66f39788be760ee4.
Revert "ascend-g300: change to b2g vendor branch"

This reverts commit a674a38a255839625ae850299c28c1bb947bb872.
Revert "Add U8815 to v1-train"

This reverts commit 34d1dac02595664a006944eda1ec63cc8263f190.