cmake: fix macho {compatibility,current} version

CMakeLists.txt

@@ -118,18 +118,14 @@ set_target_properties(SDL2_net PROPERTIES
 if(NOT ANDROID)
     set_target_properties(SDL2_net PROPERTIES
         DEBUG_POSTFIX "${SDL2NET_DEBUG_POSTFIX}"
+        SOVERSION "${LT_MAJOR}"
+        VERSION "${LT_VERSION}"
     )
     if(APPLE)
-        # the SOVERSION property corresponds to the compatibility version and VERSION corresponds to the current version
-        # https://cmake.org/cmake/help/latest/prop_tgt/SOVERSION.html#mach-o-versions
+        cmake_minimum_required(VERSION 3.17)
         set_target_properties(SDL2_net PROPERTIES
-            SOVERSION "${DYLIB_COMPATIBILITY_VERSION}"
-            VERSION "${DYLIB_CURRENT_VERSION}"
-        )
-    else()
-        set_target_properties(SDL2_net PROPERTIES
-            SOVERSION "${LT_MAJOR}"
-            VERSION "${LT_VERSION}"
+            MACHO_COMPATIBILITY_VERSION "${DYLIB_COMPATIBILITY_VERSION}"
+            MACHO_CURRENT_VERSION "${DYLIB_CURRENT_VERSION}"
         )
     endif()
 endif()