[SYCL][Test issue] Fix test-e2e/FilterSelector/select_device.cpp or replace with unit tests

[againull]

Describe the bug

Test is not executed because of incorrect REQUIRES: cpu, gpu. (no device can be both cpu and gpu)

The way this test is written requires all three - opencl:cpu, opencl:gpu, level_zero:gpu be available, so something like this might work:
REQUIRES: any-device-is-cpu, any-device-is-gpu, any-device-is-level_zero, any-device-is-opencl
but still doesn't guarantee success because it seems currently there is no way to guarantee that both opencl:gpu and opencl:cpu are present (we might have opencl:cpu and level:gpu devices only, and above requirement will still be satisfied).

Tests also contains mistakes, it can be fixed like this (but probably better to just turn it into a unit test):

// RUN: %{build} -o %t.out
// RUN: env ONEAPI_DEVICE_SELECTOR="*:*" %{run-unfiltered-devices} %t.out
// RUN: env ONEAPI_DEVICE_SELECTOR="*:cpu" %{run-unfiltered-devices} %t.out
// RUN: env ONEAPI_DEVICE_SELECTOR=level_zero:gpu %{run-unfiltered-devices} %t.out
// RUN: env ONEAPI_DEVICE_SELECTOR=opencl:gpu %{run-unfiltered-devices} %t.out
// RUN: env ONEAPI_DEVICE_SELECTOR='*:cpu;level_zero:gpu' %{run-unfiltered-devices} %t.out
//
// Checks if only specified device types can be acquired from select_device
// when ONEAPI_DEVICE_SELECTOR is set
// Checks that no device is selected when no device of desired type is
// available.
//
// REQUIRES: any-device-is-cpu, any-device-is-gpu, any-device-is-level_zero, any-device-is-opencl


#include <iostream>

#include "../helpers.hpp"
#include <sycl/detail/core.hpp>
#include <sycl/platform.hpp>

using namespace sycl;
using namespace std;

int main() {
  std::string forcedDevice = env::getVal("ONEAPI_DEVICE_SELECTOR");
  if (forcedDevice == "*:*" ||
      forcedDevice.find("level_zero:gpu") != std::string::npos) {
    device d(default_selector_v);
    string name = d.get_platform().get_info<info::platform::name>();
    assert(name.find("Level-Zero") != string::npos);
  }
  if (forcedDevice != "*:*" &&
      forcedDevice.find("opencl:gpu") != std::string::npos) {
    device d(gpu_selector_v);
    string name = d.get_platform().get_info<info::platform::name>();
    assert(name.find("OpenCL") != string::npos);
  }
  if (forcedDevice == "*:*" ||
      forcedDevice.find("cpu") != std::string::npos) {
    device d(cpu_selector_v);
  }
  if (forcedDevice.find("cpu") == std::string::npos &&
                         forcedDevice.find("opencl") == std::string::npos &&
                         forcedDevice.find("*") == std::string::npos) {
    try {
      device d(cpu_selector_v);
    } catch (...) {
      return 0; // expected
    }
    std::cerr << "Error: CPU device is found, even though it shouldn't be"
              << std::endl;
    return -1;
  }

  return 0;
}

To reproduce

Environment

Linux

Additional context

No response