Introduce build target for bundled data on Windows

On non-Windows platforms, we generate assembly to bundle ICU data.
On Windows however, we previously use a checked in icudt.dll, which
is no longer maintained.

We could use the same assembly approach if we wrap in inline assembly.

Bug: chromium:938223
Change-Id: Ieced205ae2e082a5290bd45499216c6c86751ca1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/deps/icu/+/1503032


Reviewed-by: Jungshik Shin <jshin@chromium.org>