[SYCL] Use consistent `DeviceType` across different environment variables

### Is your feature request related to a problem? Please describe

For ONEAPI_DEVICE_SELECTOR, `DeviceType` is `cpu, gpu, fpga`
For SYCL_DEVICE_ALLOWLIST, `DeviceType` is `cpu, gpu, acc, fpga`
For SYCL_REDUCTION_PREFERRED_WORKGROUP_SIZE, `DeviceType` is `cpu, gpu, acc`.

There's inconsistency in the `DeviceType` value accepted by different environment variables.

### Describe the solution you would like

Ideally, we should reconcile the discrepancy in `DeviceType` and use a consistent terminology for all the environment variables.

### Describe alternatives you have considered

_No response_

### Additional context

_No response_