Build static libs on Apple

Author: pierotofy

CMakeLists.txt

@@ -68,6 +68,8 @@ set(OBJS
 if (MSVC)
     add_library(entwine STATIC ${OBJS})
     target_link_libraries(entwine PRIVATE wsock32 ws2_32)
+elseif(APPLE)
+    add_library(entwine STATIC ${OBJS})
 else()
     add_library(entwine SHARED ${OBJS})
 endif()