ui/console: fix default VC when there are no display

When display is "none", we may still have remote displays (I think it
would be simpler if VNC/Spice were regular display btw). Return the
default VC then, and set them up to fix a regression when using remote
display and it used the TTY instead.

Fixes: https://gitlab.com/qemu-project/qemu/-/issues/1989
Fixes: commit 1bec1cc0d ("ui/console: allow to override the default VC")
Reported-by: German Maglione <gmaglione@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Thomas Huth <thuth@redhat.com>

ui/console.c

@@ -1679,19 +1679,17 @@ void qemu_display_init(DisplayState *ds, DisplayOptions *opts)
 
 const char *qemu_display_get_vc(DisplayOptions *opts)
 {
-    assert(opts->type < DISPLAY_TYPE__MAX);
-    if (opts->type == DISPLAY_TYPE_NONE) {
-        return NULL;
-    }
-    assert(dpys[opts->type] != NULL);
-    if (dpys[opts->type]->vc) {
-        return dpys[opts->type]->vc;
-    } else {
 #ifdef CONFIG_PIXMAN
-        return "vc:80Cx24C";
+    const char *vc = "vc:80Cx24C";
+#else
+    const char *vc = NULL;
 #endif
+
+    assert(opts->type < DISPLAY_TYPE__MAX);
+    if (dpys[opts->type] && dpys[opts->type]->vc) {
+        vc = dpys[opts->type]->vc;
     }
-    return NULL;
+    return vc;
 }
 
 void qemu_display_help(void)