arm64: zynqmp: Enable booting to ATF

U-Boot is now able to boot to ARM Trusted Firmware (ATF). The boot
flow is SPL(EL3) loads ATF and full u-boot and jump to ATF(EL3) which
pass control to full u-boot(EL2). This has been tested on zcu106, so
enable it in this defconfig.

To generate an image that triggers this booting flow, you need to pass
'-O arm-trusted-firmware' to mkimage.

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/configs/xilinx_zynqmp_zc1751_xm019_dc5_defconfig b/configs/xilinx_zynqmp_zc1751_xm019_dc5_defconfig
index 1c93485..7a3806c 100644
--- a/configs/xilinx_zynqmp_zc1751_xm019_dc5_defconfig
+++ b/configs/xilinx_zynqmp_zc1751_xm019_dc5_defconfig
@@ -17,6 +17,7 @@
 CONFIG_SPL_OS_BOOT=y
 CONFIG_SPL_RAM_SUPPORT=y
 CONFIG_SPL_RAM_DEVICE=y
+CONFIG_SPL_ATF=y
 CONFIG_SYS_PROMPT="ZynqMP> "
 CONFIG_CMD_MEMTEST=y
 CONFIG_SYS_ALT_MEMTEST=y