dxdiagn: Add dxdiagn.dll to DxDiag_DirectXFiles container. Create fake dll for it as well.

dlls/dxdiagn/provider.c

@@ -401,6 +401,7 @@ static HRESULT DXDiag_InitDXDiagDirectXFilesContainer(IDxDiagContainer* pSubCont
         {'d','p','n','e','t','.','d','l','l',0},
         {'d','s','o','u','n','d','.','d','l','l',0},
         {'d','s','w','a','v','e','.','d','l','l',0},
+        {'d','x','d','i','a','g','n','.','d','l','l',0},
         {'q','u','a','r','t','z','.','d','l','l',0}
     };
     WCHAR szFilePath[MAX_PATH];

tools/wine.inf.in

@@ -2262,6 +2262,7 @@ HKLM,%CurrentVersion%\Telephony\Country List\998,"SameAreaRule",,"G"
 11,,dosx.exe
 11,,dsound.dll
 11,,dsound.vxd
+11,,dxdiagn.dll
 11,,gdi32.dll
 11,,glu32.dll
 11,,hal.dll