arm: MediaTek: add basic support for MT7623 boards

This adds a general board file based on MT7623 SoCs from MediaTek.

As this u-boot is loaded by MTK proprietary preloader, there is no
low level initializtion codes.

Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Tested-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/board/mediatek/mt7623/Makefile b/board/mediatek/mt7623/Makefile
new file mode 100644
index 0000000..2b42071
--- /dev/null
+++ b/board/mediatek/mt7623/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier:	GPL-2.0
+
+obj-y += mt7623_rfb.o