Remove check for hardcoded Xwayland path in gdm.

diff --git a/daemon/gdm-local-display-factory.c b/daemon/gdm-local-display-factory.c
index 7de7b99c..065325f4 100644
--- a/daemon/gdm-local-display-factory.c
+++ b/daemon/gdm-local-display-factory.c
@@ -245,9 +245,9 @@ struct GdmDisplayServerConfiguration {
         const char *session_type;
 } display_server_configuration[] = {
 #ifdef ENABLE_WAYLAND_SUPPORT
-        { "wayland", GDM_KEY_WAYLAND_ENABLE, "/usr/bin/Xwayland", "wayland" },
+        { "wayland", GDM_KEY_WAYLAND_ENABLE, "", "wayland" },
 #endif
-        { "xorg", GDM_KEY_XORG_ENABLE, "/usr/bin/Xorg", "x11" },
+        { "xorg", GDM_KEY_XORG_ENABLE, "", "x11" },
         { NULL, NULL, NULL },
 };
 
@@ -269,9 +269,6 @@ display_server_enabled (GdmLocalDisplayFactory *factory,
                 if (!gdm_settings_direct_get_boolean (key, &enabled) || !enabled)
                         return FALSE;
 
-                if (!g_file_test (binary, G_FILE_TEST_IS_EXECUTABLE))
-                        return FALSE;
-
                 return TRUE;
         }
 
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