TI DaVinci Sonata: Add Config option for 64 bit Support

Adding the CONFIG_SYS_64BIT_VSPRINTF fot the DM644x based Sonata
Without this option enabled while performing NAND operations we will get
wrong diagnostic messages.
Example if the MTD NAND driver find a bad block while erasing from
a certain address, it will say bad block skipped at 0x00000000.

Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>

include/configs/davinci_sonata.h

@@ -125,6 +125,7 @@
 #define CONFIG_SYS_NAND_HW_ECC
 #define CONFIG_SYS_MAX_NAND_DEVICE	1	/* Max number of NAND devices */
 #define CONFIG_ENV_OFFSET		0x0	/* Block 0--not used by bootcode */
+#define CONFIG_SYS_64BIT_VSPRINTF	/* needed for nand_util.c */
 #define DEF_BOOTM		""
 #elif defined(CONFIG_SYS_USE_NOR)
 #ifdef CONFIG_NOR_UART_BOOT