spinlock: use spin_lock_init replace spin_initialize

reason:
1: spin_lock_init and spin_initialize have similar functionalities.
2: spin_lock and spin_unlock should be called in matching pairs.

Signed-off-by: hujun5 <hujun5@xiaomi.com>

libs/libc/pthread/pthread_spinlock.c

@@ -94,7 +94,7 @@ int pthread_spin_init(FAR pthread_spinlock_t *lock, int pshared)
   DEBUGASSERT(lock != NULL);
   if (lock != NULL)
     {
-      spin_initialize(&lock->sp_lock, SP_UNLOCKED);
+      spin_lock_init(&lock->sp_lock);
       lock->sp_holder = IMPOSSIBLE_THREAD;
       ret             = OK;
     }