AT91: fix mistake in at91sam9260_devices.c(spi1_hw_init)

Bits 0..3 in cs_mask = CS0..CS3 in SPI mode require it to be peripheral
Bits 4..7 in cs_mask = CS0..CS3 in GPIO mode require it to be output

Signed-off-by: Reinhard Meyer <u-boot@emk-elektronik.de>

arch/arm/cpu/arm926ejs/at91/at91sam9260_devices.c

@@ -138,7 +138,7 @@ void at91_spi1_hw_init(unsigned long cs_mask)
 		at91_set_b_periph(AT91_PIO_PORTC, 4, 1);
 	}
 	if (cs_mask & (1 << 3)) {
-		at91_set_pio_output(AT91_PIO_PORTC, 3, 1);
+		at91_set_b_periph(AT91_PIO_PORTC, 3, 1);
 	}
 	if (cs_mask & (1 << 4)) {
 		at91_set_pio_output(AT91_PIO_PORTB, 3, 1);