[OneAPI GPU] Add OneAPI (SYCL) GPU Runtime Functions.

[kranipa]

This PR introduces following changes.

1. It adds the OneAPI (SYCL) GPU runtime.
2. ./jaxlib/oneapi/ contains runtime files and necessary type aliases under vendor.h and gpu_kernel_helpers.h overloads.
3. OneAPI guards area added in gpu_kernel_helpers.cc for those functions where OneAPI/SYCL has no equivalent.

[agramesh1]

CC @penpornk

[gemini-code-assist]

Code Review

This pull request introduces OneAPI/SYCL GPU runtime wrappers for JAX, adding runtime helper functions, Bazel build targets, and mapping GPU abstractions to SYCL equivalents. The review feedback highlights a standard-compliance issue in SyclSuccess() where sycl::errc::success is used instead of the standard std::error_code(0, ::sycl::sycl_category()). Additionally, minor improvements are suggested to fix typos and update documentation comments to align with this standard-compliant implementation.

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[gemini-code-assist]

The SYCL 2020 standard (sycl::errc enum class) does not define a success error code. Using sycl::errc::success is non-standard and will cause compilation failures on standard-compliant SYCL implementations (such as OpenSYCL/hipSYCL or future conforming toolchains).

To construct a standard-compliant success std::error_code in the SYCL category, you should use std::error_code(0, sycl::sycl_category()) instead.

Suggested change

	inline std::error_code SyclSuccess() {
	return sycl::make_error_code(sycl::errc::success);
	}
	inline std::error_code SyclSuccess() {
	return std::error_code(0, ::sycl::sycl_category());
	}

[gemini-code-assist]

Update the comment to reflect the standard-compliant implementation of SyclSuccess() using sycl::sycl_category() and fix the typos ('sucess' -> 'success', 'therfore' -> 'therefore').

Suggested change

	// Reference:
	// https://github.khronos.org/SYCL_Reference/iface/exception.html#standard-sycl-error-codes
	// SYCL application never throws an exception with "sucess" error code, and no
	// other code has the value zero therfore, construct a std::error_code with
	// sycl::errc::success to represent gpuSuccess ("not an error"). Success paths
	// must return gpuSuccess (sycl category); a bare std::error_code{} is generic
	// category and will fail CHECK_EQ.
	// Reference:
	// https://github.khronos.org/SYCL_Reference/iface/exception.html#standard-sycl-error-codes
	// A standard SYCL application uses `sycl::sycl_category()` for SYCL errors.
	// Since a default-constructed `std::error_code` uses the generic category,
	// it would fail `CHECK_EQ` when compared against a SYCL error code.
	// Therefore, we construct a `std::error_code` with value `0` and the
	// `sycl::sycl_category()` to represent `gpuSuccess`.

[gemini-code-assist]

Fix typos in the comment ('has be added' -> 'has been added', 'elif DEFINED' -> 'elif defined') to improve readability and maintain professional code quality.

Suggested change

	// OneAPI/SYCL has no equivalent of cusolver/cublas/cusparse status types;
	// no ErrorString overloads will be added here.
	// The HIP ErrorString overloads were in #else rather than under a
	// JAX_GPU_HIP guard, which has be added above elif DEFINED(JAX_GPU_HIP) to
	// avoid compiling for OneAPI/SYCL.
	// OneAPI/SYCL has no equivalent of cusolver/cublas/cusparse status types;
	// no ErrorString overloads will be added here.
	// The HIP ErrorString overloads were in #else rather than under a
	// JAX_GPU_HIP guard, which has been added above with elif defined(JAX_GPU_HIP)
	// to avoid compiling for OneAPI/SYCL.