at91sam9x5: set default EBI I/O drive configuration.

This patch configure at91sam9x5's EBI drive I/O. Without this, When SD card boot, the nand flash read/write are not stable. Which will cause kernel MTD test fail (Since mainline kernel doesn't configure the EBI register).

Signed-off-by: Josh Wu <josh.wu@atmel.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>

board/atmel/at91sam9x5ek/at91sam9x5ek.c

@@ -62,6 +62,10 @@ static void at91sam9x5ek_nand_hw_init(void)
 	csa |= AT91_MATRIX_EBI_CS3A_SMC_SMARTMEDIA;
 	/* NAND flash on D16 */
 	csa |= AT91_MATRIX_NFD0_ON_D16;
+
+	/* Configure IO drive */
+	csa &= ~AT91_MATRIX_EBI_EBI_IOSR_NORMAL;
+
 	writel(csa, &matrix->ebicsa);
 
 	/* Configure SMC CS3 for NAND/SmartMedia */