Adjusting CHANGELOG to match beta branch.

Windows support for Linux ARM cross-compilation is now in the beta
branch, so adjusting the CHANGELOG to match the change that was made
along with the now-submitted cherry pick.

Change-Id: I41d9d286558bd21350d6f8f6e56115cd3031af33
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/441541
Auto-Submit: Tess Strickland <[email protected]>
Commit-Queue: Ivan Inozemtsev <[email protected]>
Reviewed-by: Ivan Inozemtsev <[email protected]>

Author: sstrickl

CHANGELOG.md

@@ -83,8 +83,6 @@ constraint][language version] lower bound to 3.9 or greater (`sdk: '^3.9.0'`).
 Added [cross-compilation][] support for
 target architectures of `arm` (ARM32) and `riscv64` (RV64GC)
 when the target OS is Linux.
-Note that Linux ARM cross-compilation is
-not available on Windows host platforms.
 
 [cross-compilation]: https://dart.dev/tools/dart-compile#cross-compilation-exe