Adds syscall for sleep and print and makes process work in user mode

src/scheduler.rs

@@ -28,14 +28,14 @@ pub static mut PROCESS_TABLE: LazyCell<[Process; PROCESSUS_COUNT]> = LazyCell::n
             mepc: core::ptr::null(),
             mstatus: 0,
         },
-        entry_point: None,
         stack: [0; _],
     })
 });
 
 pub extern "C" fn idle() {
     loop {
-        // enable_supervisor_interrupt();
+        // write_string_temp("idle");
+        // info!("idle");
         unsafe {
             wfi();
         }