x86/apic/es7000: Make apicid of a cluster (not CPU) from a cpumask

cpu_mask_to_apicid_and() always returns apicid of a single CPU,
even in case multiple CPUs were requested. This update fixes a
typo and forces apicid of a cluster to be returned.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/20120614075043.GI3383@dhcp-26-207.brq.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>