Define HAS_INTTYPES_H too, fixes new MSVC build error

syncterm\bbslist.c(778): error C2146: syntax error:
  missing ')' before identifier 'SCNx8

We aren't defining this standard format macro in gen_defs.h (maybe we should
be?) - but as long as MSVC has inttypes.h, seems we should be using that
instead.

src/xpdev/xpdev_mt.props

@@ -7,7 +7,7 @@
   </PropertyGroup>
   <ItemDefinitionGroup>
     <ClCompile>
-      <PreprocessorDefinitions>HAS_STDINT_H;XPDEV_THREAD_SAFE;LINK_LIST_THREADSAFE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>HAS_INTTYPES_H;HAS_STDINT_H;XPDEV_THREAD_SAFE;LINK_LIST_THREADSAFE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(MSBuildThisFileDirectory);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
     <Link>