Function ap_start::kstart_ap

pub fn kstart_ap(
    processor_id: u32,
    cpu_id: CpuId,
    _stack_start: VirtualAddress,
    _stack_end: VirtualAddress,
    nmi_lint: u8,
    nmi_flags: u16
) -> !

Entry to rust for an AP. The arguments must match the invocation order in “ap_boot.asm”