Remove cuda 11 specific changes from repo

[rgsl888prabhu]

Description

This PR removes CUDA 11 pertaining changes since we have moved to CUDA 12 support only

Issue

closes #220

Checklist

• I am familiar with the Contributing Guidelines.
• Testing
  • New or existing tests cover these changes
  • Added tests
  • Created an issue to follow-up
  • NA
• Documentation
  • The documentation is up to date with these changes
  • Added new documentation
  • NA

[jakirkham]

Thanks Ram! 🙏

Had a couple comments below

[jakirkham]

Recognize we are only testing CUDA 12, but could we keep this?

[rgsl888prabhu]

Since we might move to cuda 13 in 25.10 or later, I removed it just for future case.

[jakirkham]

Could we please also take a look at this code?

cuopt/cpp/src/linear_programming/utilities/ping_pong_graph.cuh

Lines 48 to 63 in 9952c26

	void end_capture(i_t total_pdlp_iterations)
	{
	if (total_pdlp_iterations % 2 == 0 && !even_initialized) {
	RAFT_CUDA_TRY(cudaStreamEndCapture(stream_view_.value(), &even_graph));
	// Extra NULL NULL 0 mandatory for cuda 11.8
	RAFT_CUDA_TRY(cudaGraphInstantiate(&even_instance, even_graph, nullptr, nullptr, 0));
	even_initialized = true;
	RAFT_CUDA_TRY_NO_THROW(cudaGraphDestroy(even_graph));
	} else if (total_pdlp_iterations % 2 == 1 && !odd_initialized) {
	RAFT_CUDA_TRY(cudaStreamEndCapture(stream_view_.value(), &odd_graph));
	// Extra NULL NULL 0 mandatory for cuda 11.8
	RAFT_CUDA_TRY(cudaGraphInstantiate(&odd_instance, odd_graph, nullptr, nullptr, 0));
	odd_initialized = true;
	RAFT_CUDA_TRY_NO_THROW(cudaGraphDestroy(odd_graph));
	}
	}

Edit: Also this CMake code

cuopt/cpp/CMakeLists.txt

Lines 222 to 224 in 47fb158

	if(CMAKE_CUDA_COMPILER_ID STREQUAL "NVIDIA" AND CMAKE_CUDA_COMPILER_VERSION VERSION_GREATER_EQUAL 11.4)
	list(PREPEND CUOPT_PRIVATE_CUDA_LIBS CUDA::cublasLt)
	endif()

[rgsl888prabhu]

Could we please also take a look at this code?

cuopt/cpp/src/linear_programming/utilities/ping_pong_graph.cuh

Lines 48 to 63 in 9952c26

	void end_capture(i_t total_pdlp_iterations)
	{
	if (total_pdlp_iterations % 2 == 0 && !even_initialized) {
	RAFT_CUDA_TRY(cudaStreamEndCapture(stream_view_.value(), &even_graph));
	// Extra NULL NULL 0 mandatory for cuda 11.8
	RAFT_CUDA_TRY(cudaGraphInstantiate(&even_instance, even_graph, nullptr, nullptr, 0));
	even_initialized = true;
	RAFT_CUDA_TRY_NO_THROW(cudaGraphDestroy(even_graph));
	} else if (total_pdlp_iterations % 2 == 1 && !odd_initialized) {
	RAFT_CUDA_TRY(cudaStreamEndCapture(stream_view_.value(), &odd_graph));
	// Extra NULL NULL 0 mandatory for cuda 11.8
	RAFT_CUDA_TRY(cudaGraphInstantiate(&odd_instance, odd_graph, nullptr, nullptr, 0));
	odd_initialized = true;
	RAFT_CUDA_TRY_NO_THROW(cudaGraphDestroy(odd_graph));
	}
	}

Yes, I am currently discussing with team on how much effort would it have and asked them to push changes to this PR. Meanwhile, I will keep don't merge tag to this.

[jakirkham]

Thanks Ram! 🙏

Can you please look at this CMake code as well?

cuopt/cpp/CMakeLists.txt

Lines 222 to 224 in 47fb158

	if(CMAKE_CUDA_COMPILER_ID STREQUAL "NVIDIA" AND CMAKE_CUDA_COMPILER_VERSION VERSION_GREATER_EQUAL 11.4)
	list(PREPEND CUOPT_PRIVATE_CUDA_LIBS CUDA::cublasLt)
	endif()

[rgsl888prabhu]

Thanks Ram! 🙏

Can you please look at this CMake code as well?

cuopt/cpp/CMakeLists.txt

Lines 222 to 224 in 47fb158

	if(CMAKE_CUDA_COMPILER_ID STREQUAL "NVIDIA" AND CMAKE_CUDA_COMPILER_VERSION VERSION_GREATER_EQUAL 11.4)
	list(PREPEND CUOPT_PRIVATE_CUDA_LIBS CUDA::cublasLt)
	endif()

Removed if conditions around it.

[rgsl888prabhu]

@jakirkham May I get another set of review and also had few questions on previous reviews

[akifcorduk]

Looks good on cpp side.

[bdice]

One small suggestion to clarify a comment, otherwise LGTM. We should land this soon for 25.08.

[rgsl888prabhu]

/merge

[jakirkham]

Thanks Ram and thanks to all the reviewers! 🙏

Agree this looks good