automation: disable xen,enhanced in qemu-smoke-arm64

Disable xen,enhanced because we don't use PV drivers in this test and
also because the kernel used for testing is old and unpatched and would
break if xen,enhanced is passed.

This patch unbreaks gitlab-ci.

Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
Reviewed-by: Ayan Kumar Halder <ayankuma@amd.com>
Tested-by: Ayan Kumar Halder <ayankuma@amd.com>

automation/scripts/qemu-smoke-arm64.sh

@@ -83,6 +83,7 @@ NUM_DOMUS=1
 DOMU_KERNEL[0]="Image"
 DOMU_RAMDISK[0]="initrd"
 DOMU_MEM[0]="256"
+DOMU_ENHANCED[0]=0
 
 LOAD_CMD="tftpb"
 UBOOT_SOURCE="boot.source"