language: update IANA entries Required larger size for region group bitmasks. Change-Id: I8e58c359d3ee0221477994425b35519c5a8ef843 Reviewed-on: https://go-review.googlesource.com/55751 Run-TryBot: Marcel van Lohuizen <mpvl@golang.org> Reviewed-by: Nigel Tao <nigeltao@golang.org>