[PATCH] fix MTIME_SEC_MAX on 32-bit

The maximum seconds value we can handle on 32bit is LONG_MAX.

Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>