x86: use reboot_type on EFI 32

This patch makes reboot_type of BOOT_EFI is used on i386 too. Because
correpsonding reboot code of i386 and x86_64 is merged.

Signed-off-by: Huang Ying <ying.huang@intel.com>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>