[BUG] Realtek 0bda:c811 (Cudy AC650/WU650) does not work on linux-cachyos 7.1.3-2 but works on linux-cachyos-lts 6.18

### Pre-flight checklist

- [x] I have searched existing issues and this is not a duplicate.
- [x] I have read the [Contributing Guidelines](https://github.com/CachyOS/linux-cachyos/blob/master/CONTRIBUTING.md).
- [x] I have verified the issue is reproducible with the latest available CachyOS kernel.
- [x] I have tried to reproduce the issue on Arch Linux's `linux` kernel.

### Upstream / vanilla kernel check

I tested with a vanilla/upstream kernel and the issue does NOT reproduce there (CachyOS-specific bug)

### Kernel variant

linux-cachyos (EEVDF, Clang)

### System information (cachyos-bugreport.sh)

```text
https://paste.cachyos.org/p/bf15f4e.log
```

### Manual system information (if cachyos-bugreport.sh is unavailable)

```text

```

### Bug description

My Cudy WU650 (Realtek 0bda:c811) USB Wi-Fi adapter is not detected correctly when using the linux-cachyos 7.1.3-2 kernel.

The device is detected by lsusb, but no wireless interface is created, and NetworkManager does not show any Wi-Fi device.

I tested the adapter with:

linux-cachyos 7.1.3-2: Wi-Fi does not work.
linux-cachyos-lts 6.18.38-2: Wi-Fi works, although the connection is unstable.
Lubuntu (kernel 7.0.0-27-generic): Wi-Fi works correctly.

I also tried the rtl8821cu-morrownr-dkms-git driver. It fails to build on the 7.1.3-2 kernel due to kernel API changes, but it builds and works on the LTS kernel.

This appears to be a regression affecting the Realtek 0bda:c811 chipset on the linux-cachyos 7.1 kernel.

### Steps to reproduce

1_Install CachyOS with the linux-cachyos 7.1.3-2 kernel.
2_Connect a Cudy WU650 USB Wi-Fi adapter (Realtek 0bda:c811).
3_Boot the system.
4_Check ip link or NetworkManager.
5_No wireless interface is created, although lsusb detects the USB device.

### Expected behavior

The Wi-Fi adapter should be detected automatically, a wireless interface should be created, and available Wi-Fi networks should appear in NetworkManager, just like they do on linux-cachyos-lts 6.18 and Lubuntu (kernel 7.0.0-27-generic).

### Actual behavior

The USB adapter is detected by lsusb (Realtek 0bda:c811), but no wireless interface is created. ip link only shows the Ethernet interfaces, and NetworkManager does not detect any Wi-Fi device. Loading the rtl8xxxu module does not help. The rtl8821cu-morrownr-dkms-git driver also fails to build on the linux-cachyos 7.1.3-2 kernel, while it builds and works on the LTS kernel.

### Logs / stack traces

```text
[ 4.069746] usb 1-9: new high-speed USB device number 4 using xhci_hcd
[ 4.276782] usb 1-9: New USB device found, idVendor=0bda, idProduct=c811, bcdDevice=2.00
[ 4.276789] usb 1-9: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 4.276792] usb 1-9: Product: 802.11ac NIC
[ 4.276794] usb 1-9: Manufacturer: Realtek
[ 4.276796] usb 1-9: SerialNumber: 123456

The USB device is detected correctly by the kernel, but no wireless interface (wlan*) is created and NetworkManager does not detect any Wi-Fi device.
```

### Additional system information

System information:

- Distribution: CachyOS (Arch Linux)
- Kernel: 7.1.3-2-cachyos
- Desktop Environment: KDE Plasma 6.7.2 (Wayland)
- Init system: systemd 261
- CPU: AMD Ryzen 5 8500G
- GPU: AMD Radeon 740M (amdgpu)
- RAM: 16 GB
- Motherboard: Gigabyte A620M H (UEFI F31)
- Wi-Fi adapter: Cudy AC650 (Realtek USB, ID 0bda:c811)
- Driver tested: rtl8821cu-morrownr-dkms-git 5.12.0.4.210.7f63a9d-1
- Ethernet: Realtek RTL8111/8168 (r8169)

Additional notes:

- The adapter is detected by lsusb as Realtek 0bda:c811.
- On kernel 7.1.3-2-cachyos, the DKMS driver (rtl8821cu-morrownr-dkms-git) fails to build because of kernel API changes, with errors such as:
- no member named 'tag' in 'struct pppoe_hdr'
- no member named 'tag_data' in 'struct pppoe_tag'
- Because the module cannot be built, no Wi-Fi driver is loaded and no wireless interface is created.
- The same adapter works with CachyOS LTS (Linux 6.18.x), although performance is limited.
- The adapter also works correctly on Lubuntu using kernel 7.0.0-27-generic.