"[PATCH] Fix leak on /proc/lockdep_stats" fixed 5 leaks which happen if one
uses single_open() as .open function and seq_release() as .release function.

Let's add small amount of runtime checking.

Sample output is:

	memory leak: 'timer_list'
	WARNING: at fs/seq_file.c:289 seq_release()
	 [<c015e311>] seq_release+0x53/0x68
	 [<c0171bd8>] proc_reg_release+0x63/0x74
	 [<c0149877>] __fput+0x28/0xd3
	 [<c0147681>] filp_close+0x48/0x4f
	 [<c014876a>] sys_close+0x74/0xbe
	 [<c010248e>] sysenter_past_esp+0x5f/0x85
	 =======================
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>