don't open-code file_inode()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index 0d302a8..99401ef 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -548,8 +548,8 @@
 	exe_file = get_task_exe_file(tsk);
 	if (!exe_file)
 		return 0;
-	ino = exe_file->f_inode->i_ino;
-	dev = exe_file->f_inode->i_sb->s_dev;
+	ino = file_inode(exe_file)->i_ino;
+	dev = file_inode(exe_file)->i_sb->s_dev;
 	fput(exe_file);
 	return audit_mark_compare(mark, ino, dev);
 }