x86, apic: Fix false positive section mismatch in numaq_32.c

The variable apic_numaq placed in noninit section references the
function wakeup_secondary_cpu_via_nmi(), which is in __cpuinit
section. Thus causes a section mismatch warning. To avoid such
mismatch we mark apic_numaq as __refdata.

We were warned by the following warning:

  WARNING: arch/x86/kernel/built-in.o(.data+0x932c): Section mismatch in
  reference from the variable apic_numaq to the function
  .cpuinit.text:wakeup_secondary_cpu_via_nmi()

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
LKML-Reference: <b9df5fa10907120407p6b4f67dtf4d563155488188a@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>