libxl: vga.kind none when no device specified

When no video device is specified in config we should set both
hvm.nographic to 1 and hvm.vga.kind to NONE.

Without hvm.vga.kind=LIBXL_VGA_INTERFACE_TYPE_NONE both -nographic and
-device 'cirrus-vga' are on qemu cmdline.
Signed-off-by: NArtur Puzio <contact@puzio.waw.pl>
Reviewed-by: NJim Fehlig <jfehlig@suse.com>

src/libxl/libxl_conf.c

@@ -2404,6 +2404,7 @@ libxlMakeVideo(virDomainDefPtr def, libxl_domain_config *d_config)
         b_info->video_memkb = def->videos[0]->vram;
     } else {
         libxl_defbool_set(&b_info->u.hvm.nographic, 1);
+        b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_NONE;
     }
 
     return 0;

tests/libxlxml2domconfigdata/fullvirt-acpi-slic.json

@@ -20,6 +20,9 @@
             "acpi": "True",
             "acpi_firmware": "/path/to/slic.dat",
             "nographic": "True",
+            "vga": {
+                "kind": "none"
+            },
             "vnc": {
                 "enable": "False"
             },

tests/libxlxml2domconfigdata/fullvirt-cpuid.json

@@ -27,6 +27,9 @@
             "apic": "True",
             "acpi": "True",
             "nographic": "True",
+            "vga": {
+                "kind": "none"
+            },
             "vnc": {
                 "enable": "False"
             },