build: Remove obsolete soup dependency

It's unused since commit 96396163c ...

https://gitlab.gnome.org/GNOME/gnome-shell/issues/574

meson.build

@@ -95,7 +95,6 @@ cogl_dep = dependency(cogl_pc, version: mutter_req)
 cogl_pango_dep = dependency(cogl_pango_pc, version: mutter_req)
 mutter_dep = dependency(libmutter_pc, version: mutter_req)
 polkit_dep = dependency('polkit-agent-1', version: polkit_req)
-soup_dep = dependency('libsoup-2.4')
 startup_dep = dependency('libstartup-notification-1.0', version: startup_req)
 ibus_dep = dependency('ibus-1.0', version: ibus_req)
 x11_dep = dependency('x11')

src/meson.build

@@ -45,7 +45,6 @@ gnome_shell_deps = [
   atk_bridge_dep,
   gjs_dep,
   gdk_x11_dep,
-  soup_dep,
   clutter_dep,
   cogl_pango_dep,
   startup_dep,
@@ -224,8 +223,7 @@ libshell_dep = declare_dependency(link_with: libshell)
 libshell_gir_includes = [
   'Clutter-@0@'.format(mutter_api_version),
   'ClutterX11-@0@'.format(mutter_api_version),
-  'Meta-@0@'.format(mutter_api_version),
-  'Soup-2.4'
+  'Meta-@0@'.format(mutter_api_version)
 ]
 
 if have_networkmanager

src/shell-util.h

@@ -5,7 +5,6 @@
 
 #include <gio/gio.h>
 #include <clutter/clutter.h>
-#include <libsoup/soup.h>
 #include <gdk-pixbuf/gdk-pixbuf.h>
 #include <meta/meta-cursor-tracker.h>
 #include <meta/meta-window-actor.h>