vnc: drop QERR_VNC_SERVER_FAILED

We now always return "nice" error messages in errp when we goto fail.
Drop the default error message.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qerror.h

@@ -237,9 +237,6 @@ void assert_no_error(Error *err);
 #define QERR_VIRTFS_FEATURE_BLOCKS_MIGRATION \
     ERROR_CLASS_GENERIC_ERROR, "Migration is disabled when VirtFS export path '%s' is mounted in the guest using mount_tag '%s'"
 
-#define QERR_VNC_SERVER_FAILED \
-    ERROR_CLASS_GENERIC_ERROR, "Could not start VNC server on %s"
-
 #define QERR_SOCKET_CONNECT_FAILED \
     ERROR_CLASS_GENERIC_ERROR, "Failed to connect to socket"
 

ui/vnc.c

@@ -3088,9 +3088,6 @@ void vnc_display_open(DisplayState *ds, const char *display, Error **errp)
     return;
 
 fail:
-    if (!error_is_set(errp)) {
-        error_set(errp, QERR_VNC_SERVER_FAILED, display);
-    }
     g_free(vs->display);
     vs->display = NULL;
 }