kb9202 board: fix build problem.

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/include/configs/kb9202.h b/include/configs/kb9202.h
index 75d9c3b..7dcce83 100644
--- a/include/configs/kb9202.h
+++ b/include/configs/kb9202.h
@@ -54,10 +54,13 @@
 
 #define	CFG_LONGHELP
 
+#ifndef roundup
+#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
+#endif
 /*
  * Size of malloc() pool
  */
-#define CFG_MALLOC_LEN	(CFG_ENV_SIZE + 128*1024)
+#define CFG_MALLOC_LEN	(roundup(CFG_ENV_SIZE,4096) + 128*1024)
 #define CFG_GBL_DATA_SIZE	128	/* size in bytes reserved for initial data */
 
 #define CONFIG_BAUDRATE 115200