[gdm] manager: fix compile warning

[Ray Strode <halfline src gnome org>]

commit 13e71c2825ecc83f841a14153ea4cf5e330c9fef
Author: Ray Strode <rstrode redhat com>
Date:   Fri Oct 13 16:41:02 2017 -0400

    manager: fix compile warning
    
    commit 7e8243eecd0233f7ab92519207f2520794439b11 introduced a
    compiler warning if gdm is built with --enable-wayland and
    --disable-user-display-server
    
    This commit fixes that.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=788963

 daemon/gdm-manager.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/daemon/gdm-manager.c b/daemon/gdm-manager.c
index c3293d9..9f06196 100644
--- a/daemon/gdm-manager.c
+++ b/daemon/gdm-manager.c
@@ -2304,7 +2304,7 @@ create_user_session_for_display (GdmManager *manager,
         char       *display_auth_file = NULL;
         char       *display_seat_id = NULL;
         char       *display_id = NULL;
-#ifdef ENABLE_WAYLAND_SUPPORT
+#if defined(ENABLE_WAYLAND_SUPPORT) && defined(ENABLE_USER_DISPLAY_SERVER)
         char       *display_session_type = NULL;
         gboolean    greeter_is_wayland;
 #endif
@@ -2316,7 +2316,7 @@ create_user_session_for_display (GdmManager *manager,
                       "remote-hostname", &remote_hostname,
                       "x11-authority-file", &display_auth_file,
                       "seat-id", &display_seat_id,
-#ifdef ENABLE_WAYLAND_SUPPORT
+#if defined(ENABLE_WAYLAND_SUPPORT) && defined(ENABLE_USER_DISPLAY_SERVER)
                       "session-type", &display_session_type,
 #endif
                       NULL);