[newlib-cygwin] Cygwin: fpathconf: update _PC_ASYNC_IO return value

[Yaakov Selkowitz]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=7e09931ad95a10d15b7a93b49faeadfe25f63464

commit 7e09931ad95a10d15b7a93b49faeadfe25f63464
Author: Yaakov Selkowitz <yselkowi@redhat.com>
Date:   Wed Jul 25 15:00:43 2018 -0500

    Cygwin: fpathconf: update _PC_ASYNC_IO return value
    
    Signed-off-by: Yaakov Selkowitz <yselkowi@redhat.com>

Diff:
---
 winsup/cygwin/fhandler.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/winsup/cygwin/fhandler.cc b/winsup/cygwin/fhandler.cc
index ded12cc..22dbdb0 100644
--- a/winsup/cygwin/fhandler.cc
+++ b/winsup/cygwin/fhandler.cc
@@ -1875,6 +1875,7 @@ fhandler_base::fpathconf (int v)
       set_errno (EINVAL);
       break;
     case _PC_ASYNC_IO:
+      return 1;
     case _PC_PRIO_IO:
       break;
     case _PC_SYNC_IO: