add virtual PLIC related EmulatedDeviceType

[liulog]

Add virtual PLIC related EmulatedDeviceType （PPPTGlobal = 0x30）

pub enum EmulatedDeviceType {
    ......
    // Arch-specific interrupt controller devices.
    // 0x20 - 0x22: GPPT (GIC Partial Passthrough) devices.
    /// ARM GIC Partial Passthrough Redistributor device.
    GPPTRedistributor = 0x20,
    /// ARM GIC Partial Passthrough Distributor device.
    GPPTDistributor = 0x21,
    /// ARM GIC Partial Passthrough Interrupt Translation Service device.
    GPPTITS = 0x22,
    // 0x30: PPPT (PLIC Partial Passthrough) devices.
    PPPTGlobal = 0x30,
    ......
}

This is used for axdevice to emulate PLIC and axvisor's vm config about emu_devices field.

# Emu_devices.
# Name Base-Ipa Ipa_len Alloc-Irq Emu-Type EmuConfig.
emu_devices = [
    ["plic", 0x0c00_0000, 0x60_0000, 0, 0x30, [2]],     # [context_num]
]