Kernel: SpinLocks now reschedule if they cannot aquire the lock

This allows us to not actually spin doing nothing while waiting for
another (not executing) to release the lock. This api won't probably
work when we get to SMP

kernel/kernel/SpinLock.cpp

@@ -8,7 +8,7 @@ namespace Kernel
 	{
 		while (__sync_lock_test_and_set(&m_lock, 1))
 			while (m_lock)
-				__builtin_ia32_pause();
+				Scheduler::get().reschedule();
 	}
 
 	void SpinLock::unlock()
@@ -27,10 +27,6 @@ namespace Kernel
 
 		while (true)
 		{
-			// Wait for us to be the locker or the lock being free
-			while (m_locker != -1 && m_locker != tid)
-				__builtin_ia32_pause();
-
 			m_lock.lock();
 			if (m_locker == tid)
 			{