ARM: imx: Add QSPI boot mode for i.MX6UL/ULL

This patch adds the missing boot mode detection for QSPI boot on
i.MX6UL/ULL. Without it, booting with SPL from QSPI NOR does not work.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Stefano Babic <sbabic@denx.de>

arch/arm/mach-imx/spl.c

@@ -94,6 +94,11 @@ u32 spl_boot_device(void)
 	/* NAND Flash: 8.5.2, Table 8-10 */
 	case IMX6_BMODE_NAND_MIN ... IMX6_BMODE_NAND_MAX:
 		return BOOT_DEVICE_NAND;
+#if defined(CONFIG_MX6UL) || defined(CONFIG_MX6ULL)
+	/* QSPI boot */
+	case IMX6_BMODE_QSPI:
+		return BOOT_DEVICE_SPI;
+#endif
 	}
 	return BOOT_DEVICE_NONE;
 }