[BUG] RN2483 hangs on read

### Description / Steps to reproduce the issue

The RN2483 with the `rn2xx3` driver hangs on read

The following is the problematic part, situated in `rn2xx3_read()`
```
ret = file_read(&priv->uart, &hex_byte, 2);
if (ret < 2)
{
goto early_ret;
}
```

The device seems to always return 1 byte of data instead of 2, thus hanging the system

Switching to a double single byte read fixed the issue
```
ret = file_read(&priv->uart, &hex_byte, 1);
if (ret < 1)
{
goto early_ret;
}
ret = file_read(&priv->uart, &hex_byte[1], 1);
if (ret < 1)
{
goto early_ret;
}
```

I do not find this to be an elegant solution, is there a different read function that could wait until the buffer is full?

### On which OS does this issue occur?

[OS: Mac]

### What is the version of your OS?

MacOS 15.6.1

### NuttX Version

releases/12.12

### Issue Architecture

[Arch: arm64]

### Issue Area

[Area: Drivers]

### Host information

_No response_

### Verification

- [x] I have verified before submitting the report.