sh: Renesas RSK+ 7203 board support

This adds initial support for the RTE RSK+ SH7203 board.

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 368a0c9..09bd2f5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -753,12 +753,14 @@
 	MIGO-R		SH7722
 
 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
+		  <iwamatsu.nobuhiro@renesas.com>
 
 	MS7750SE	SH7750
 	MS7722SE	SH7722
 	R7780MP		SH7780
 	R2DPlus		SH7751R
 	SH7763RDP	SH7763
+	RSK7203		SH7203
 
 Mark Jonas <mark.jonas@de.bosch.com>