Add DAP items to NEWS

Now that DAP is in GDB 14, significant changes to it should be noted
in NEWS.  This patch adds a note for a fix that's already gone in.  I
started a new section in NEWS because more changes are coming.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30473
Approved-By: Eli Zaretskii <eliz@gnu.org>