[hid_core] fix NPad crash on pikmin 4 due to nullref (#4249)

Signed-off-by: lizzie <lizzie@eden-emu.dev>

- [x] I have read and followed the [Contribution Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/CONTRIBUTING.md#code-contributions).
- [x] I have read and followed the [AI Policy](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/AI.md)
- [x] I have read and followed the [Coding Guidelines](https://git.eden-emu.dev/eden-emu/eden/src/branch/master/docs/policies/Coding.md) to the best of my ability.

-------------------

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4249
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Reviewed-by: Maufeat <sahyno1996@gmail.com>

src/hid_core/resources/npad/npad.cpp

@@ -504,9 +504,12 @@ void NPad::OnUpdate(Kernel::KernelCore& kernel, const Core::Timing::CoreTiming&
 
         for (std::size_t i = 0; i < controller_data[aruid_index].size(); ++i) {
             auto& controller = controller_data[aruid_index][i];
-            controller.shared_memory =
-                &data->shared_memory_format->npad.npad_entry[i].internal_state;
+            controller.shared_memory = &data->shared_memory_format->npad.npad_entry[i].internal_state;
             auto* npad = controller.shared_memory;
+            if (!npad || !controller.device) {
+                LOG_WARNING(Service_HID, "No device for {}", i);
+                continue;
+            }
 
             const auto& controller_type = controller.device->GetNpadStyleIndex();