arm: rmobile: koelsch: Enable CONFIG_SYS_GENERIC_BOARD

Add CONFIG_SYS_GENERIC_BOARD to use common/board_*.c for koelsch.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
diff --git a/include/configs/koelsch.h b/include/configs/koelsch.h
index d7a0c2d..6795f28 100644
--- a/include/configs/koelsch.h
+++ b/include/configs/koelsch.h
@@ -41,6 +41,7 @@
 
 #define CONFIG_SYS_TEXT_BASE	0xE6304000
 #define CONFIG_SYS_THUMB_BUILD
+#define CONFIG_SYS_GENERIC_BOARD
 
 /* Support File sytems */
 #define CONFIG_DOS_PARTITION