Fix Compliation warning for TNY-A9260 and TNY-A9G20

The patch fixes a compilation warning by defining
CONFIG_SYS_64BIT_VSPRINTF in the config file

Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
diff --git a/include/configs/tny_a9260.h b/include/configs/tny_a9260.h
index 4ad081b..5b70a7b 100644
--- a/include/configs/tny_a9260.h
+++ b/include/configs/tny_a9260.h
@@ -138,6 +138,7 @@
 #define CONFIG_ENV_OFFSET 0x60000
 #define CONFIG_ENV_OFFSET_REDUND 0x80000
 #define CONFIG_ENV_SIZE 0x20000
+#define CONFIG_SYS_64BIT_VSPRINTF	/* needed for nand_util.c */
 #endif
 
 #define CONFIG_BOOTCOMMAND	"nboot 0x21000000 0 400000"