Kernel: Make PageTable::s_fast_page_lock non-recursive

This lock is only used in wrapper of PageTable. There is no possiblity
of taking the lock outside of these wrappers.

kernel/include/kernel/Memory/PageTable.h

@@ -130,7 +130,7 @@ namespace Kernel
 	private:
 		paddr_t						m_highest_paging_struct { 0 };
 		mutable RecursiveSpinLock	m_lock;
-		static RecursiveSpinLock	s_fast_page_lock;
+		static SpinLock				s_fast_page_lock;
 	};
 
 	static constexpr size_t range_page_count(vaddr_t start, size_t bytes)