feat(getc with semanphore implemented, everything works as expected)

src/keyboard.c

@@ -99,7 +99,7 @@ void add_to_queue(unsigned char c)
         keyboard_queue.array[keyboard_queue.first_free] = c;
         keyboard_queue.first_free = (keyboard_queue.first_free + 1) % QUEUE_SIZE;
         keyboard_queue.cpt++;
-        // sem_up(&keyboard_sem);
+        sem_up(&keyboard_sem);
     }
 
     irq_enable();
@@ -112,7 +112,7 @@ char getc()
     char c = NONE;
     if (keyboard_queue.cpt)
     {
-        // sem_down(&keyboard_sem);
+        sem_down(&keyboard_sem);
         int idx = (keyboard_queue.first_free + QUEUE_SIZE - keyboard_queue.cpt) % QUEUE_SIZE;
         c = keyboard_queue.array[idx];
         keyboard_queue.cpt--;