Merge branch 'fix_knowhere_merge' into 'branch-0.4.0'

MS-442 fix merge error

See merge request megasearch/milvus!455

Former-commit-id: 40c61fa15a7335643d071be527dc0a5684cf98cf

cpp/src/core/src/knowhere/index/vector_index/gpu_ivf.cpp

@@ -123,6 +123,7 @@ void GPUIVF::search_impl(int64_t n,
                          int64_t *labels,
                          const Config &cfg) {
     if (auto device_index = std::static_pointer_cast<faiss::gpu::GpuIndexIVF>(index_)) {
+        // todo: allocate search memory
         auto nprobe = cfg.get_with_default("nprobe", size_t(1));
 
         std::lock_guard<std::mutex> lk(mutex_);

cpp/src/core/test/test_nsg/CMakeLists.txt

@@ -27,6 +27,8 @@ aux_source_directory(${CMAKE_SOURCE_DIR}/src/knowhere/index/vector_index/nsg nsg
 set(interface_src
         ${CMAKE_SOURCE_DIR}/src/knowhere/index/vector_index/ivf.cpp
         ${CMAKE_SOURCE_DIR}/src/knowhere/index/vector_index/gpu_ivf.cpp
+        ${CMAKE_SOURCE_DIR}/src/knowhere/index/vector_index/cloner.cpp
+        ${CMAKE_SOURCE_DIR}/src/knowhere/index/vector_index/idmap.cpp
         ${CMAKE_SOURCE_DIR}/src/knowhere/index/vector_index/nsg_index.cpp
         ${CMAKE_SOURCE_DIR}/src/knowhere/adapter/structure.cpp
         ${CMAKE_SOURCE_DIR}/src/knowhere/common/exception.cpp