Kernel: Update comment about what the MM lock protects

Kernel/Memory/MemoryManager.cpp

@@ -62,8 +62,6 @@ static MemoryManager* s_the;
 
 // The MM lock protects:
 // - all data members of MemoryManager
-// - the quickmap mechanism
-// - the PTE/PDE mapping mechanism
 RecursiveSpinlock s_mm_lock { LockRank::MemoryManager };
 
 MemoryManager& MemoryManager::the()