sh: Add support Renesas Solutions Migo-R board

Migo-R is a board based on SH7722 and has may devices.
In this patch, supported SCIF, NOR flash and Ethernet.

Signed-off-by: Yusuke Goda <goda.yusuke@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index e31ea06..6fc1e60 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -703,6 +703,10 @@
 
 	MS7720SE		SH7720
 
+Yusuke Goda <goda.yusuke@renesas.com>
+
+	MIGO-R			SH7722
+
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 # Blackfin Systems:							#
 #									#