[SYCL][NFC] Fix duplication caused by functors defined in ext::oneapi…

[v-klochkov]

… and sycl

The functors ext::oneapi::minimum/maximum were defined identically to
sycl::minimum/maximum. Turn them into aliases of functors defined in sycl.
Remove duplicated checks for ext::oneapi functors.

Signed-off-by: Vyacheslav N Klochkov [email protected]

[v-klochkov]

The only failed test is: SYCL-on-device::gpu.cpp
That test fail is unrelated to this patch and the test fails for all PRs created recently

[romanovvlad]

@v-klochkov
Isn't ext::oneapi::bit_or a public interface? If so, removing it breaks API backward compatibility.

[v-klochkov]

@v-klochkov
Isn't ext::oneapi::bit_or a public interface? If so, removing it breaks API backward compatibility.

@romanovvlad This patch does not remove anything from ext::oneapi namespace. Before this patch both sycl::bit_or and ext::oneapi::bit_or were aliased to std::bit_or. That is not changed in this patch, I only removed duplicated checks:
(std::is_same<T, sycl::bit_or> || std::is_same<T, ext::oneapi::bit_or>) ==> (std::is_same<T, sycl::bit_or>).

The second change is the replacement of the duplicate struct ext::oneapi::minimum (identical to sycl::minimum) with alias to sycl::minimum. It does not remove anything and thus does not break API compatibility.