qprocess: don't leak pid pipe if redirection fails in startDetached()

Change-Id: Ifc42f634964b9412f73f53fb20bd220fcbd9a86c
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/io/qprocess_unix.cpp

@@ -925,6 +925,8 @@ bool QProcessPrivate::startDetached(qint64 *pid)
         closeChannel(&stdinChannel);
         closeChannel(&stdoutChannel);
         closeChannel(&stderrChannel);
+        qt_safe_close(pidPipe[0]);
+        qt_safe_close(pidPipe[1]);
         qt_safe_close(startedPipe[0]);
         qt_safe_close(startedPipe[1]);
         return false;