MAINTAINERS: Add myself as devicetree-rebasing maintainer

Add myself as devicetree-rebasing maintainer.

Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 0b08ca1..6541ab2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -989,6 +989,11 @@
 F:	common/cyclic.c
 F:	include/cyclic.h
 
+DEVICETREE REBASING SUBTREE
+M:	Sumit Garg <sumit.garg@linaro.org>
+S:	Maintained
+F:	dts/upstream/
+
 DFU
 M:	Lukasz Majewski <lukma@denx.de>
 M:	Mattijs Korpershoek <mkorpershoek@baylibre.com>