[PATCH] x86_64: Don't call enforce_max_cpus when hotplug is enabled

enforce_max_cpus nukes out cpu_present_map and cpu_possible_map making it
impossible to add new cpus in the system.  Since it doesnt provide any
additional value apart this call and reference is removed.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>