correct file name to common name and update Simplified Chinese translation text

if specify the language use Chinese in BoardConfig.mk or vendorsetup.sh, old file name is confusing, and incompatible with twrp device tree. use the common name, making one device tree more flexible to be used in different recovery project.

Make the text more Chinese and fewer errors, vocabulary unified. btw: your crowdin system is too old and out of date, hard to use, and showing wrong results after uploading translation file, the translated text often goes to another wrong line（Traditional Chinese text is especially disastrous), then cannot edit. So I had to make a new merge request on gitlab.com