x86: Clean up lapic codes

x86: Clean up lapic codes

This commit cleans up the lapic codes:
- Delete arch/x86/include/asm/lapic_def.h, and move register and bit
  defines into arch/x86/include/asm/lapic.h
- Use MSR defines from msr-index.h in enable_lapic() and disable_lapic()
- Remove unnecessary stuff like NEED_LAPIC, X86_GOOD_APIC and
  CONFIG_AP_IN_SIPI_WAIT
- Move struct x86_cpu_priv defines to asm/arch-ivybridge/bd82x6x.h, as
  it is not apic related and only used by ivybridge
- Fix coding convention issues

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>