KVM: Make kvm_mmu_slot_remove_write_access() take mmu_lock by itself

Better to place mmu_lock handling and TLB flushing code together since
this is a self-contained function.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>

arch/x86/kvm/x86.c

@@ -6899,11 +6899,8 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
 	 * Existing largepage mappings are destroyed here and new ones will
 	 * not be created until the end of the logging.
 	 */
-	if (npages && (mem->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
-		spin_lock(&kvm->mmu_lock);
+	if (npages && (mem->flags & KVM_MEM_LOG_DIRTY_PAGES))
 		kvm_mmu_slot_remove_write_access(kvm, mem->slot);
-		spin_unlock(&kvm->mmu_lock);
-	}
 	/*
 	 * If memory slot is created, or moved, we need to clear all
 	 * mmio sptes.