add w600 support

w600 is a wifi soc from winner micro(www.winnermicro.com).

Change-Id: Ib8ccd6e52baefca6547fb97d29db75db0ee73948
Signed-off-by: Simon Qian <versaloon@simonqian.com>
Reviewed-on: http://openocd.zylin.com/4801
Tested-by: jenkins
Reviewed-by: yichen <wdyichen@wdyichen.cn>
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

src/flash/nor/Makefile.am

@@ -63,6 +63,7 @@ NOR_DRIVERS = \
 	%D%/str9xpec.c \
 	%D%/tms470.c \
 	%D%/virtual.c \
+	%D%/w600.c \
 	%D%/xcf.c \
 	%D%/xmc1xxx.c \
 	%D%/xmc4xxx.c