libglnx porting: gs_fd_close -> glnx_fd_close

I'd like to eventually kill libgsystem.

src/libostree/ostree-repo-pull.c

@@ -795,7 +795,7 @@ meta_fetch_on_complete (GObject           *object,
   OstreeObjectType objtype;
   GError *local_error = NULL;
   GError **error = &local_error;
-  gs_fd_close int fd = -1;
+  glnx_fd_close int fd = -1;
 
   ostree_object_name_deserialize (fetch_data->object, &checksum, &objtype);
   g_debug ("fetch of %s%s complete", ostree_object_to_string (checksum, objtype),
@@ -950,7 +950,7 @@ static_deltapart_fetch_on_complete (GObject           *object,
   g_autoptr(GVariant) part = NULL;
   GError *local_error = NULL;
   GError **error = &local_error;
-  gs_fd_close int fd = -1;
+  glnx_fd_close int fd = -1;
 
   g_debug ("fetch static delta part %s complete", fetch_data->expected_checksum);
 

src/libostree/ostree-repo-static-delta-compilation.c

@@ -456,7 +456,7 @@ get_unpacked_unlinked_content (OstreeRepo       *repo,
 {
   gboolean ret = FALSE;
   g_autofree char *tmpname = g_strdup ("tmpostree-deltaobj-XXXXXX");
-  gs_fd_close int fd = -1;
+  glnx_fd_close int fd = -1;
   g_autoptr(GBytes) ret_content = NULL;
   g_autoptr(GInputStream) istream = NULL;
   g_autoptr(GFileInfo) ret_finfo = NULL;

src/libostree/ostree-repo.c

@@ -2884,7 +2884,7 @@ ostree_repo_load_file (OstreeRepo         *self,
               guint32 mode;
               g_autoptr(GVariant) metadata = NULL;
               g_autoptr(GBytes) bytes = NULL;
-              gs_fd_close int fd = -1;
+              glnx_fd_close int fd = -1;
 
               bytes = ot_lgetxattrat (self->objects_dir_fd, loose_path_buf,
                                       "user.ostreemeta", error);
@@ -2943,7 +2943,7 @@ ostree_repo_load_file (OstreeRepo         *self,
               if (g_file_info_get_file_type (ret_file_info) == G_FILE_TYPE_REGULAR
                   && (out_input || out_xattrs))
                 {
-                  gs_fd_close int fd = -1;
+                  glnx_fd_close int fd = -1;
 
                   if (!gs_file_openat_noatime (self->objects_dir_fd, loose_path_buf, &fd,
                                                cancellable, error))
@@ -4630,7 +4630,7 @@ ostree_repo_regenerate_summary (OstreeRepo     *self,
         gs_free char *to = NULL;
         gs_free guchar *csum = NULL;
         gs_free char *superblock = NULL;
-        gs_fd_close int superblock_file_fd = -1;
+        glnx_fd_close int superblock_file_fd = -1;
         g_autoptr(GInputStream) in_stream = NULL;
 
         _ostree_parse_delta_name (delta_names->pdata[i], &from, &to);