[newlib-cygwin] Cygwin: Document recent bug fix in release note.

[Takashi Yano]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=ad75a40cd80bf266dfa5201497c53b7060f7b86d

commit ad75a40cd80bf266dfa5201497c53b7060f7b86d
Author: Takashi Yano <takashi.yano@nifty.ne.jp>
Date:   Sat Feb 3 23:37:46 2024 +0900

    Cygwin: Document recent bug fix in release note.

Diff:
---
 winsup/cygwin/release/3.5.1 | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/winsup/cygwin/release/3.5.1 b/winsup/cygwin/release/3.5.1
new file mode 100644
index 000000000..054988b90
--- /dev/null
+++ b/winsup/cygwin/release/3.5.1
@@ -0,0 +1,5 @@
+Bug Fixes
+---------
+
+- Fix exit code for non-cygwin process running in console. The bug
+  was introduced in 3.5.0.