[PATCH] cpuset: mempolicy migration typo fix

Mistyped an ifdef CONFIG_CPUSETS - fixed.

I doubt that anyone ever noticed.  The impact of this typo was
that if someone:
 1) was using MPOL_BIND to force off node allocations
 2) while using cpusets to constrain memory placement
 3) when that cpuset was migrating that jobs memory
 4) while the tasks in that job were actively forking
then there was a rare chance that future allocations using
that MPOL_BIND policy would be node local, not off node.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>