Kernel: Stub more functions to progress aarch64 build

Author: https://github.com/FireFox317
Commit: 32f4c8df6c
Pull-request: https://github.com/SerenityOS/serenity/pull/15794
Reviewed-by: https://github.com/nico ✅

Kernel/Storage/StorageManagement.cpp

@@ -102,11 +102,16 @@ UNMAP_AFTER_INIT void StorageManagement::enumerate_pci_controllers(bool force_pi
                 }
             }
 
-#if ARCH(I386) || ARCH(X86_64)
             auto subclass_code = static_cast<SubclassID>(device_identifier.subclass_code().value());
+#if ARCH(I386) || ARCH(X86_64)
             if (subclass_code == SubclassID::IDEController && kernel_command_line().is_ide_enabled()) {
                 m_controllers.append(PCIIDELegacyModeController::initialize(device_identifier, force_pio));
             }
+#elif ARCH(AARCH64)
+            (void)force_pio;
+            TODO_AARCH64();
+#else
+#    error Unknown architecture
 #endif
 
             if (subclass_code == SubclassID::SATAController