Kernel: Take EnumerableDeviceIdentifier by const ref instead of by value

It's 48 bytes.

Kernel/Bus/PCI/Access.cpp

@@ -160,7 +160,7 @@ UNMAP_AFTER_INIT void Access::rescan_hardware()
     SpinlockLocker scan_locker(m_scan_lock);
     VERIFY(m_device_identifiers.is_empty());
     for (auto& [_, host_controller] : m_host_controllers) {
-        host_controller->enumerate_attached_devices([this](EnumerableDeviceIdentifier device_identifier) {
+        host_controller->enumerate_attached_devices([this](EnumerableDeviceIdentifier const& device_identifier) {
             auto device_identifier_or_error = DeviceIdentifier::from_enumerable_identifier(device_identifier);
             if (device_identifier_or_error.is_error()) {
                 dmesgln("Failed during PCI Access::rescan_hardware due to {}", device_identifier_or_error.error());

Kernel/Bus/PCI/Controller/HostController.cpp

@@ -54,7 +54,7 @@ u16 HostController::read16_field(BusNumber bus, DeviceNumber device, FunctionNum
     return read16_field(bus, device, function, to_underlying(field));
 }
 
-UNMAP_AFTER_INIT void HostController::enumerate_functions(Function<void(EnumerableDeviceIdentifier)> const& callback, BusNumber bus, DeviceNumber device, FunctionNumber function, bool recursive_search_into_bridges)
+UNMAP_AFTER_INIT void HostController::enumerate_functions(Function<void(EnumerableDeviceIdentifier const&)> const& callback, BusNumber bus, DeviceNumber device, FunctionNumber function, bool recursive_search_into_bridges)
 {
     dbgln_if(PCI_DEBUG, "PCI: Enumerating function, bus={}, device={}, function={}", bus, device, function);
     Address address(domain_number(), bus.value(), device.value(), function.value());
@@ -83,7 +83,7 @@ UNMAP_AFTER_INIT void HostController::enumerate_functions(Function<void(Enumerab
     }
 }
 
-UNMAP_AFTER_INIT void HostController::enumerate_device(Function<void(EnumerableDeviceIdentifier)> const& callback, BusNumber bus, DeviceNumber device, bool recursive_search_into_bridges)
+UNMAP_AFTER_INIT void HostController::enumerate_device(Function<void(EnumerableDeviceIdentifier const&)> const& callback, BusNumber bus, DeviceNumber device, bool recursive_search_into_bridges)
 {
     dbgln_if(PCI_DEBUG, "PCI: Enumerating device in bus={}, device={}", bus, device);
     if (read16_field(bus, device, 0, PCI::RegisterOffset::VENDOR_ID) == PCI::none_value)
@@ -97,14 +97,14 @@ UNMAP_AFTER_INIT void HostController::enumerate_device(Function<void(EnumerableD
     }
 }
 
-UNMAP_AFTER_INIT void HostController::enumerate_bus(Function<void(EnumerableDeviceIdentifier)> const& callback, BusNumber bus, bool recursive_search_into_bridges)
+UNMAP_AFTER_INIT void HostController::enumerate_bus(Function<void(EnumerableDeviceIdentifier const&)> const& callback, BusNumber bus, bool recursive_search_into_bridges)
 {
     dbgln_if(PCI_DEBUG, "PCI: Enumerating bus {}", bus);
     for (u8 device = 0; device < 32; ++device)
         enumerate_device(callback, bus, device, recursive_search_into_bridges);
 }
 
-UNMAP_AFTER_INIT void HostController::enumerate_attached_devices(Function<void(EnumerableDeviceIdentifier)> callback)
+UNMAP_AFTER_INIT void HostController::enumerate_attached_devices(Function<void(EnumerableDeviceIdentifier const&)> callback)
 {
     VERIFY(Access::the().access_lock().is_locked());
     VERIFY(Access::the().scan_lock().is_locked());

Kernel/Bus/PCI/Controller/HostController.h

@@ -31,12 +31,12 @@ public:
 
     u32 domain_number() const { return m_domain.domain_number(); }
 
-    void enumerate_attached_devices(Function<void(EnumerableDeviceIdentifier)> callback);
+    void enumerate_attached_devices(Function<void(EnumerableDeviceIdentifier const&)> callback);
 
 private:
-    void enumerate_bus(Function<void(EnumerableDeviceIdentifier)> const& callback, BusNumber, bool recursive);
-    void enumerate_functions(Function<void(EnumerableDeviceIdentifier)> const& callback, BusNumber, DeviceNumber, FunctionNumber, bool recursive);
-    void enumerate_device(Function<void(EnumerableDeviceIdentifier)> const& callback, BusNumber bus, DeviceNumber device, bool recursive);
+    void enumerate_bus(Function<void(EnumerableDeviceIdentifier const&)> const& callback, BusNumber, bool recursive_search_into_bridges);
+    void enumerate_functions(Function<void(EnumerableDeviceIdentifier const&)> const& callback, BusNumber, DeviceNumber, FunctionNumber, bool recursive_search_into_bridges);
+    void enumerate_device(Function<void(EnumerableDeviceIdentifier const&)> const& callback, BusNumber bus, DeviceNumber device, bool recursive_search_into_bridges);
 
     u8 read8_field(BusNumber, DeviceNumber, FunctionNumber, RegisterOffset field);
     u16 read16_field(BusNumber, DeviceNumber, FunctionNumber, RegisterOffset field);