Removing hnswlib stuff

cpp/CMakeLists.txt

@@ -49,7 +49,6 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 option(BUILD_SHARED_LIBS "Build raft shared libraries" ON)
 option(BUILD_TESTS "Build raft unit-tests" ON)
 option(BUILD_PRIMS_BENCH "Build raft C++ benchmark tests" OFF)
-option(BUILD_CAGRA_HNSWLIB "Build CAGRA+hnswlib interface" ON)
 option(CUDA_ENABLE_KERNELINFO "Enable kernel resource usage info" OFF)
 option(CUDA_ENABLE_LINEINFO
        "Enable the -lineinfo option for nvcc (useful for cuda-memcheck / profiler)" OFF
@@ -172,10 +171,6 @@ if(BUILD_PRIMS_BENCH)
   rapids_cpm_gbench(BUILD_STATIC)
 endif()
 
-if(BUILD_CAGRA_HNSWLIB)
-  include(cmake/thirdparty/get_hnswlib.cmake)
-endif()
-
 # ##################################################################################################
 # * raft ---------------------------------------------------------------------
 add_library(raft INTERFACE)
@@ -184,9 +179,6 @@ add_library(raft::raft ALIAS raft)
 target_include_directories(
   raft INTERFACE "$<BUILD_INTERFACE:${RAFT_SOURCE_DIR}/include>" "$<INSTALL_INTERFACE:include>"
 )
-if(BUILD_CAGRA_HNSWLIB)
-  target_link_libraries(raft INTERFACE hnswlib::hnswlib)
-endif()
 
 # Keep RAFT as lightweight as possible. Only CUDA libs and rmm should be used in global target.
 target_link_libraries(raft INTERFACE rmm::rmm cuco::cuco nvidia::cutlass::cutlass CCCL::CCCL)