did some restructuring, got multitasking almost working

kernel/lib/tasks.c

@@ -0,0 +1,11 @@
+#include <lib/tasks.h>
+
+void spin_lock(spinlock_t *lock) {
+    while (__sync_lock_test_and_set(&lock->locked, 1)) {
+        asm volatile("pause"); 
+    }
+}
+
+void spin_unlock(spinlock_t *lock) {
+    __sync_lock_release(&lock->locked);
+}