sbbscon (sbbs.exe) wasn't being built with mosquitto lib support on Windows

src/sbbs3/sbbscon.vcxproj

@@ -38,6 +38,7 @@
     <Import Project="..\build\target_ia32.props" />
     <Import Project="..\xpdev\xpdev_mt.props" />
     <Import Project="..\hash\hash.props" />
+    <Import Project="..\..\3rdp\win32.release\mosquitto\mosquitto.props" />
   </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
@@ -48,6 +49,7 @@
     <Import Project="..\build\target_ia32.props" />
     <Import Project="..\xpdev\xpdev_mt.props" />
     <Import Project="..\hash\hash.props" />
+    <Import Project="..\..\3rdp\win32.release\mosquitto\mosquitto.props" />
   </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup>
@@ -148,6 +150,7 @@
   </ItemDefinitionGroup>
   <ItemGroup>
     <ClCompile Include="getctrl.c" />
+    <ClCompile Include="ringbuf.c" />
     <ClCompile Include="sbbs_ini.c">
       <AdditionalIncludeDirectories Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <PreprocessorDefinitions Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">%(PreprocessorDefinitions)</PreprocessorDefinitions>