win32: add test_def to vs project files

ports/win32/msvc/lwip_unittests.vcxproj

@@ -85,6 +85,7 @@
   <ItemGroup>
     <ClCompile Include="..\..\..\..\lwip\test\unit\api\test_sockets.c" />
     <ClCompile Include="..\..\..\..\lwip\test\unit\arch\sys_arch.c" />
+    <ClCompile Include="..\..\..\..\lwip\test\unit\core\test_def.c" />
     <ClCompile Include="..\..\..\..\lwip\test\unit\core\test_mem.c" />
     <ClCompile Include="..\..\..\..\lwip\test\unit\core\test_pbuf.c" />
     <ClCompile Include="..\..\..\..\lwip\test\unit\ip4\test_ip4.c" />
@@ -101,6 +102,7 @@
   <ItemGroup>
     <ClInclude Include="..\..\..\..\lwip\test\unit\api\test_sockets.h" />
     <ClInclude Include="..\..\..\..\lwip\test\unit\arch\sys_arch.h" />
+    <ClInclude Include="..\..\..\..\lwip\test\unit\core\test_def.h" />
     <ClInclude Include="..\..\..\..\lwip\test\unit\core\test_mem.h" />
     <ClInclude Include="..\..\..\..\lwip\test\unit\core\test_pbuf.h" />
     <ClInclude Include="..\..\..\..\lwip\test\unit\ip4\test_ip4.h" />

ports/win32/msvc/lwip_unittests.vcxproj.filters

@@ -73,6 +73,9 @@
     <ClCompile Include="..\..\..\..\lwip\test\unit\ip4\test_ip4.c">
       <Filter>ip4</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\..\..\lwip\test\unit\core\test_def.c">
+      <Filter>core</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\..\..\..\lwip\test\unit\core\test_mem.h">
@@ -116,5 +119,8 @@
     <ClInclude Include="..\..\..\..\lwip\test\unit\ip4\test_ip4.h">
       <Filter>ip4</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\..\..\lwip\test\unit\core\test_def.h">
+      <Filter>core</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>