conf: cleanup macros lxc_chroot

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

src/lxc/conf.c

@@ -1349,7 +1349,6 @@ int lxc_chroot(const struct lxc_rootfs *rootfs)
 	int i, ret;
 	char *p, *p2;
 	char buf[LXC_LINELEN];
-	FILE *f;
 	char *root = rootfs->mount;
 
 	nroot = realpath(root, NULL);
@@ -1388,6 +1387,7 @@ int lxc_chroot(const struct lxc_rootfs *rootfs)
 	 * inherited mounts are locked and we should live with all this trash.
 	 */
 	for (;;) {
+		__do_fclose FILE *f = NULL;
 		int progress = 0;
 
 		f = fopen("./proc/self/mountinfo", "r");
@@ -1421,8 +1421,6 @@ int lxc_chroot(const struct lxc_rootfs *rootfs)
 				progress++;
 		}
 
-		fclose(f);
-
 		if (!progress)
 			break;
 	}