Disable the lockdown backend, which depends on GNOME

... and has an identical implementation in xdg-desktop-portal-gnome.

Fallout from bf54024610

https://src.fedoraproject.org/rpms/xdg-desktop-portal-gtk/pull-request/3

xdg-desktop-portal-gtk.spec

@@ -3,7 +3,7 @@
 
 Name:           xdg-desktop-portal-gtk
 Version:        1.12.0
-Release:        2%{?dist}
+Release:        3%{?dist}
 Summary:        Backend implementation for xdg-desktop-portal using GTK+
 
 License:        LGPLv2+
@@ -44,6 +44,7 @@ A backend implementation for xdg-desktop-portal that is using GTK+.
     --enable-appchooser \
     --enable-settings \
     --disable-background \
+    --disable-lockdown \
     --disable-screencast \
     --disable-screenshot \
     --disable-wallpaper
@@ -74,6 +75,9 @@ A backend implementation for xdg-desktop-portal that is using GTK+.
 
 
 %changelog
+* Tue Feb 08 2022 Debarshi Ray <rishi@fedoraproject.org> - 1.12.0-3
+- Disable the lockdown backend, which depends on GNOME
+
 * Sat Jan 22 2022 Fedora Release Engineering <releng@fedoraproject.org> - 1.12.0-2
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_36_Mass_Rebuild