Cygwin: pipe: Fix performance degradation for non-cygwin pipe.

Cygwin: pipe: Fix performance degradation for non-cygwin pipe.

https://cygwin.com/pipermail/cygwin/2022-December/252628.html

After the commit 9e4d308cd592, the performance of read from non-cygwin
pipe has been degraded. This is because select_sem mechanism does not
work for non-cygwin pipe. This patch fixes the issue.

Fixes: 9e4d308cd592 ("Cygwin: pipe: Adopt FILE_SYNCHRONOUS_IO_NONALERT
flag for read pipe.")
Reported-by: tryandbuy <tryandbuy@proton.me>
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>