Broken links in `EUC_JP` encoding doc

[Mingun]

EUC_JP doc refers to the euc-jp.html and euc-jp-bmp.html, which are not exist. According to the https://encoding.spec.whatwg.org/#indexes I assume, that the correct link is https://encoding.spec.whatwg.org/jis0212.html and https://encoding.spec.whatwg.org/jis0212-bmp.html

[hsivonen]

Yeah, EUC-JP should link to the pages you point out and also to https://encoding.spec.whatwg.org/jis0208.html and https://encoding.spec.whatwg.org/jis0208-bmp.html . Looks like I need to revive a way to run the Python 2-dependent generation script.