Add support for `shieldt ablet`

### Is your device already requested?

- [x] I have searched the existing issues

### Brand

nvidia

### Name

shield tablet

### Device code

shield

### Model

_No response_

### Device images

```Markdown

```

### Do you own the device and would be willing to test the installer?

- [x] I own the device and am willing to test the installer on it.

### Additional context

```Markdown

```