feat(reset): Added restart return type

[stabl-gjn]

Related issue: #382

Explicitly set the return type of reset::restart as the never type.
This is already correctly set on the generated ffi bindings:

extern "C" {
    #[doc = " @brief  Restart PRO and APP CPUs.\n\n This function can be called both from PRO and APP CPUs.\n After successful restart, CPU reset reason will be SW_CPU_RESET.\n Peripherals (except for WiFi, BT, UART0, SPI1, and legacy timers) are not reset.\n This function does not return."]
    pub fn esp_restart() -> !;
}

[ivmarkov]

Yes, why not? Thanks!