sh: Add support ESPT-GIGA borad

ESPT-Giga is SH7763-based reference board.
Board support is relatively sparse, presently supporting serial,
gigabit ethernet, USB host, and MTD.

More information (in Japanese) available at:
http://www.cente.jp/product/cente_hard/ESPT-Giga.html

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/Makefile b/Makefile
index 8d05103..0d607ca 100644
--- a/Makefile
+++ b/Makefile
@@ -3545,6 +3545,11 @@
 	@echo "#define CONFIG_AP325RXA 1" > $(obj)include/config.h
 	@$(MKCONFIG) -a $(@:_config=) sh sh4 ap325rxa renesas
 
+espt_config  :   unconfig
+	@mkdir -p $(obj)include
+	@echo "#define CONFIG_ESPT 1" > $(obj)include/config.h
+	@$(MKCONFIG) -a $(@:_config=) sh sh4 espt
+
 #========================================================================
 # SPARC
 #========================================================================