[libchamplain] Simplify an if in meson

[Jiří Techet <jiritechet src gnome org>]

commit ad67be60cb386e83dbfd1032cd99c762df3badb1
Author: Jiří Techet <techet gmail com>
Date:   Thu Feb 7 13:46:08 2019 +0100

    Simplify an if in meson

 meson.build | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)
---
diff --git a/meson.build b/meson.build
index ede3214..318b110 100644
--- a/meson.build
+++ b/meson.build
@@ -108,9 +108,7 @@ if build_gtk_doc and not gtk_doc_dep.found()
 endif
 
 build_gtk_widgetry = get_option('widgetry')
-if build_gtk_widgetry and not gtk_dep.found()
-  build_gtk_widgetry = false
-elif build_gtk_widgetry and not clutter_gtk_dep.found()
+if build_gtk_widgetry and not (gtk_dep.found() and clutter_gtk_dep.found())
   build_gtk_widgetry = false
 endif