x86, apic: Add boot_cpu_is_bsp() to check if boot cpu is BSP

Kexec can enter the kdump 2nd kernel on AP if crash happens on AP. To
check if boot cpu is BSP, introduce a helper function
boot_cpu_is_bsp().

Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/20130829092758.5476.90694.stgit@localhost6.localdomain6
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
3 files changed