[gtkmm] docs/reference/meson.build: Improve the update for Doxygen >= 1.8.16

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 34b1d9a4d9ef4fc31b5a0f64ccaf88476777a9db
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Wed Jun 17 15:57:05 2020 +0200

    docs/reference/meson.build: Improve the update for Doxygen >= 1.8.16
    
    Move some code from meson.build to doc-install.pl (in mm-common),
    where regular expressions can be used.

 docs/reference/meson.build | 12 ------------
 1 file changed, 12 deletions(-)
---
diff --git a/docs/reference/meson.build b/docs/reference/meson.build
index ad35111e..1e4c523d 100644
--- a/docs/reference/meson.build
+++ b/docs/reference/meson.build
@@ -28,20 +28,8 @@ foreach module : tag_file_modules
     elif htmlrefdir == ''
       htmlrefdir = htmlrefpub
     endif
-    if htmlrefpub.startswith('/')
-      htmlrefpub = 'file://' + htmlrefpub
-    endif
-    if htmlrefdir.startswith('/')
-      htmlrefdir = 'file://' + htmlrefdir
-    endif
     doxygen_tagfiles += ' "' + doxytagfile + '=' + htmlrefpub + '"'
 
-    if not htmlrefdir.endswith('/')
-      htmlrefdir += '/'
-    endif
-    if not htmlrefpub.endswith('/')
-      htmlrefpub += '/'
-    endif
     # Doxygen <= 1.8.15
     docinstall_flags += ['-l', doxytagfile.split('/')[-1] + '@' + htmlrefdir]
     if htmlrefpub != htmlrefdir