try workaround for windows

This commit adds ggml.c to the test-backend-ops compilation unit as on
windows the linker cannot resolve some of the functions that have been
moved into test-backend-ops, like ggml_hash_set_new. I'm not sure we
will keep this moving but for now this will at least allow the test to
be run on windows as well.

Author: danbev

tests/CMakeLists.txt

@@ -202,6 +202,8 @@ if (NOT LLAMA_SANITIZE_ADDRESS)
 endif()
 llama_build_and_test(test-gguf.cpp)
 llama_build_and_test(test-backend-ops.cpp)
+target_sources(test-backend-ops PRIVATE ${PROJECT_SOURCE_DIR}/ggml/src/ggml.c)
+target_compile_definitions(test-backend-ops PRIVATE GGML_BUILD GGML_VERSION=\"${GGML_VERSION}\" GGML_COMMIT=\"${GGML_COMMIT}\")
 target_include_directories(test-backend-ops PRIVATE ${PROJECT_SOURCE_DIR}/ggml/src)
 
 llama_build_and_test(test-model-load-cancel.cpp  LABEL "model")