net: fastboot: Merge AOSP UDP fastboot

Merge UDP fastboot support from AOSP:

  https://android.googlesource.com/platform/external/u-boot/+/android-o-mr1-iot-preview-8

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
Signed-off-by: Alex Deymo <deymo@google.com>
Signed-off-by: Jocelyn Bohr <bohr@google.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

include/net/fastboot.h

@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (C) 2016 The Android Open Source Project
+ */
+
+#ifndef __NET_FASTBOOT_H__
+#define __NET_FASTBOOT_H__
+
+/**********************************************************************/
+/*
+ *	Global functions and variables.
+ */
+
+/**
+ * Wait for incoming fastboot comands.
+ */
+void fastboot_start_server(void);
+
+/**********************************************************************/
+
+#endif /* __NET_FASTBOOT_H__ */