x86: Update io_apic.c to use new cpumask API

Impact: cleanup, consolidate patches, use new API

Consolidate the following into a single patch to adapt to new
sparseirq code in arch/x86/kernel/io_apic.c, add allocation of
cpumask_var_t's in domain and old_domain, and reduce further
merge conflicts.  Only one file (arch/x86/kernel/io_apic.c) is
changed in all of these patches.

	0006-x86-io_apic-change-irq_cfg-domain-old_domain-to.patch
	0007-x86-io_apic-set_desc_affinity.patch
	0008-x86-io_apic-send_cleanup_vector.patch
	0009-x86-io_apic-eliminate-remaining-cpumask_ts-from-st.patch
	0021-x86-final-cleanups-in-io_apic-to-use-new-cpumask-AP.patch
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>