ARM: at91: spl: Add boot device for boot from QSPI

Add the boot device for booting from the QSPI flash.

Signed-off-by: Wenyou Yang <wenyou.yang@microchip.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-at91/spl.c b/arch/arm/mach-at91/spl.c
index e113336..98337ae 100644
--- a/arch/arm/mach-at91/spl.c
+++ b/arch/arm/mach-at91/spl.c
@@ -56,6 +56,8 @@
 	if (dev == ATMEL_SAMA5_BOOT_FROM_SPI)
 		return BOOT_DEVICE_SPI;
 #endif
+	if (dev == ATMEL_SAMA5_BOOT_FROM_QSPI)
+		return BOOT_DEVICE_SPI;
 
 	if (dev == ATMEL_SAMA5_BOOT_FROM_SMC)
 		return BOOT_DEVICE_NAND;