Tweak ICU data build settings to include more locale information

[anarchodin]

In looking at Deno, I discovered that its Intl seems to share Chrome's non-support for Icelandic.

Since both Node and Edge do support Icelandic, it's clearly not a limitation of V8 as such. In Chrome's case, Google appear to specifically disable support for locales that don't have a full interface translation, which seems like a silly thing to do for a browser. Does Deno inherit that butchered ICU for some reason?