x86, mce: mce_intel.c needs <asm/apic.h>

mce_intel.c uses apic_write() and lapic_get_maxlvt(), and so it needs
<asm/apic.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>