Function exit_current_process

pub fn exit_current_process(
    exit_code: i32,
    all_state: &mut InterruptAllSavedState,
)

Exit the current process, and move the all_state to the scheduler. The caller of this function (i.e. interrupt) will use the all_state to go back to the scheduler. This function will remove the context from the CPU, and thus the value in all_state will be dropped.