msvc: add ip4 unit test files

ports/win32/msvc/lwip_unittests.vcxproj

@@ -87,6 +87,7 @@
     <ClCompile Include="..\..\..\..\lwip\test\unit\arch\sys_arch.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" />
     <ClCompile Include="..\..\..\..\lwip\test\unit\mdns\test_mdns.c" />
     <ClCompile Include="..\..\..\..\lwip\test\unit\mqtt\test_mqtt.c" />
     <ClCompile Include="..\..\..\..\lwip\test\unit\tcp\tcp_helper.c" />
@@ -102,6 +103,7 @@
     <ClInclude Include="..\..\..\..\lwip\test\unit\arch\sys_arch.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" />
     <ClInclude Include="..\..\..\..\lwip\test\unit\mdns\test_mdns.h" />
     <ClInclude Include="..\..\..\..\lwip\test\unit\mqtt\test_mqtt.h" />
     <ClInclude Include="..\..\..\..\lwip\test\unit\tcp\tcp_helper.h" />

ports/win32/msvc/lwip_unittests.vcxproj.filters

@@ -28,6 +28,9 @@
     <Filter Include="mqtt">
       <UniqueIdentifier>{fd48ae04-ec85-478f-a97c-a7c8384a2d94}</UniqueIdentifier>
     </Filter>
+    <Filter Include="ip4">
+      <UniqueIdentifier>{fe93fc95-f1af-4a1f-a086-c1771dbf4d79}</UniqueIdentifier>
+    </Filter>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\..\..\lwip\test\unit\core\test_mem.c">
@@ -67,6 +70,9 @@
     <ClCompile Include="..\..\..\..\lwip\test\unit\mqtt\test_mqtt.c">
       <Filter>mqtt</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\..\..\lwip\test\unit\ip4\test_ip4.c">
+      <Filter>ip4</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\..\..\..\lwip\test\unit\core\test_mem.h">
@@ -107,5 +113,8 @@
     <ClInclude Include="..\..\..\..\lwip\test\unit\mqtt\test_mqtt.h">
       <Filter>mqtt</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\..\..\lwip\test\unit\ip4\test_ip4.h">
+      <Filter>ip4</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>