[network-manager-sstp/gtk4-work] Disable these rules if not configured with GTK4

[Eivind Næss <eivnaes src gnome org>]

commit f32cf6c08602834f93431a42e486fdce57020ccd
Author: Eivind Næss <eivnaes yahoo com>
Date:   Sun Apr 3 13:32:36 2022 -0700

    Disable these rules if not configured with GTK4
    
    Signed-off-by: Eivind Næss <eivnaes yahoo com>

 Makefile.am | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/Makefile.am b/Makefile.am
index 48127e0..46acb01 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -139,6 +139,7 @@ gtk4/resources.c: properties/gresource.xml $(shell $(GLIB_COMPILE_RESOURCES) --g
        @mkdir -p $(builddir)/gtk4
        $(AM_V_GEN) $(GLIB_COMPILE_RESOURCES) $< --target=$@ --sourcedir=$(srcdir)/gtk4 
--sourcedir=$(builddir)/gtk4 --generate-source --internal
 
+if WITH_GTK4
 gtk4/%.ui: properties/%.ui
        @mkdir -p $(builddir)/gtk4
        gtk4-builder-tool simplify --3to4 $< |grep -v can-default >$@
@@ -147,6 +148,7 @@ gtk4/%.ui: properties/%.ui
 # https://gitlab.gnome.org/GNOME/gtk/-/merge_requests/4415
 EXTRA_DIST += \
        gtk4/nm-sstp-dialog.ui
+endif
 
 plugin_sources = \
        shared/nm-utils/nm-vpn-plugin-macros.h \