api: include the rundll32 helpers the MSVC-typical way

Signed-off-by: Simon Rozman <simon@rozman.si>

api/adapter.c

@@ -1653,7 +1653,7 @@ cleanupMutex:
     return RET_ERROR(Adapter, LastError);
 }
 
-#include "rundll32.h"
+#include "rundll32_i.c"
 
 _Return_type_success_(return != NULL) WINTUN_ADAPTER *WINAPI WintunCreateAdapter(
     _In_z_ const WCHAR *Pool,

api/api.vcxproj

@@ -106,7 +106,7 @@
       <PreprocessorDefinitions>_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="Exists('$(OutDir)whql\')">HAVE_WHQL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/volatile:iso %(AdditionalOptions)</AdditionalOptions>
-	  <AdditionalIncludeDirectories>..\$(Configuration)\$(WintunPlatform);..\$(Configuration);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <AdditionalIncludeDirectories>..\$(Configuration)\$(WintunPlatform);..\$(Configuration);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
     <ResourceCompile>
       <AdditionalIncludeDirectories>..\$(Configuration)\$(WintunPlatform);..\$(Configuration);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
@@ -163,7 +163,9 @@ lib.exe /def:"$(ProjectDir)nci.def" /out:"$(IntDir)nci.lib" /machine:$(PlatformT
     <ClInclude Include="entry.h" />
     <ClInclude Include="adapter.h" />
     <ClInclude Include="elevate.h" />
-    <ClInclude Include="rundll32.h" />
+    <ClInclude Include="rundll32_i.c">
+      <ExcludedFromBuild>true</ExcludedFromBuild>
+    </ClInclude>
     <ClInclude Include="logger.h" />
     <ClInclude Include="namespace.h" />
     <ClInclude Include="nci.h" />

api/api.vcxproj.filters

@@ -55,12 +55,12 @@
     <ClInclude Include="entry.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <ClInclude Include="rundll32.h">
-      <Filter>Header Files</Filter>
-    </ClInclude>
     <ClInclude Include="ntdll.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="rundll32_i.c">
+      <Filter>Source Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="namespace.c">