wasi-nn: apply the shared library hack to darwin as well (#4374)

copied from the linux version.

i'm a bit skeptical with this workaround though.
it might be simpler to prohibit the use of wamr api in these
shared libraries. after all, what these libraries do is nothing
specific to wasm.

product-mini/platforms/darwin/CMakeLists.txt

@@ -114,6 +114,12 @@ set (CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS}")
 
 set (CMAKE_MACOSX_RPATH True)
 
+# if enable wasi-nn, both wasi-nn-backends and iwasm
+# need to use same WAMR (dynamic) libraries
+if (WAMR_BUILD_WASI_NN EQUAL 1)
+  set (BUILD_SHARED_LIBS ON)
+endif ()
+
 set (WAMR_ROOT_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../../..)
 
 include (${WAMR_ROOT_DIR}/build-scripts/runtime_lib.cmake)