hostapd: Set stdout line-buffered

If hostapd will use stdout for debugging, set stdout to be line
buffered in case its output is redirected to a file. This allows
incremental output to be viewed immediately instead of at the file
buffering interval.

Signed-hostap: Paul Stewart <pstew@chromium.org>

src/utils/wpa_debug.c

@@ -574,6 +574,14 @@ void wpa_debug_close_file(void)
 #endif /* CONFIG_DEBUG_FILE */
 }
 
+
+void wpa_debug_setup_stdout(void)
+{
+#ifndef _WIN32
+	setvbuf(stdout, NULL, _IOLBF, 0);
+#endif /* _WIN32 */
+}
+
 #endif /* CONFIG_NO_STDOUT_DEBUG */