libxl: support QXL video device

libxl recently gained support for QXL video device.  Support
it in the libxl driver too.
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

src/libxl/libxl_conf.c

@@ -1741,6 +1741,17 @@ libxlMakeVideo(virDomainDefPtr def, libxl_domain_config *d_config)
             }
             break;
 
+#ifdef LIBXL_HAVE_QXL
+        case VIR_DOMAIN_VIDEO_TYPE_QXL:
+            b_info->u.hvm.vga.kind = LIBXL_VGA_INTERFACE_TYPE_QXL;
+            if (def->videos[0]->vram < 128 * 1024) {
+                virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                               _("videoram must be at least 128MB for QXL"));
+                return -1;
+            }
+            break;
+#endif
+
         default:
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                            _("video type %s is not supported by libxl"),

src/libxl/libxl_domain.c

@@ -324,6 +324,10 @@ libxlDomainDeviceDefPostParse(virDomainDeviceDefPtr dev,
                     dev->data.video->vram = 4 * 1024;
             }
             break;
+        case VIR_DOMAIN_VIDEO_TYPE_QXL:
+            if (dev->data.video->vram == 0)
+                dev->data.video->vram = 128 * 1024;
+            break;
         }
     }