NAND: Fix warning Please define CONFIG_SYS_64BIT_VSPRINTF...

Commit 8d2effea added a warning for configurations that use NAND
without defining the (then necessary) CONFIG_SYS_64BIT_VSPRINTF but
failed to fix the affected boards.

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/include/configs/socrates.h b/include/configs/socrates.h
index 5b91b4d..35feed0 100644
--- a/include/configs/socrates.h
+++ b/include/configs/socrates.h
@@ -188,6 +188,8 @@
 #define CONFIG_SYS_MAX_NAND_DEVICE	1
 #define CONFIG_CMD_NAND
 
+#define CONFIG_SYS_64BIT_VSPRINTF	/* needed for nand_util.c */
+
 /* LIME GDC */
 #define CONFIG_SYS_LIME_BASE		0xc8000000
 #define CONFIG_SYS_LIME_SIZE		0x04000000	/* 64 MB	*/