ssfn: try making normal renderer work (i hope google won't dmca this for adding noto inside lol)

kernel/src/lib/spinlock.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include <stdint.h>
+
+typedef struct spinlock
+{
+    volatile int locked;
+} spinlock_t;
+
+inline void spinlock_acquire(spinlock_t *lock) {
+    while (__sync_lock_test_and_set(&(lock)->locked, 1))
+        while ((lock)->locked)
+            __asm__ volatile("pause");
+}
+
+inline void spinlock_release(spinlock_t *lock) {
+    __sync_lock_release(&(lock)->locked);
+}