sh: Add support shmin board

This adds support for the SHMIN SH7706 board(T-SH7706LAN).
The CPU of this board is SH7706.
There are SDRAM of 32M byte, Flash memory of 512K byte, Serial,
10Base Ether and MMC.

http://web.kyoto-inet.or.jp/people/takagaki/T-SH7706/T-SH7706.htm

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 553930a..d7cd09c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1011,6 +1011,7 @@
 	SH7763RDP	SH7763
 	RSK7203		SH7203
 	AP325RXA	SH7723
+	SHMIN		SH7706
 
 Mark Jonas <mark.jonas@de.bosch.com>