Fix for win32/configure.js and WITH_THREAD_ALLOC

Building git master gives me the following error on Windows; this patch
fixes it:

	icl /EP /nologo /I..\include /D "NOLIBTOOL" /D "_REENTRANT"
libxml2.def.
src > int.msvc\libxml2.def
libxml2.def.src
Z:\...\libxml2-git8123c4f6_debug\win32\../include/libxml/xmlversion.h(105):
error: unrecognized token
  #if @WITH_THREAD_ALLOC@
      ^
Z:\...\libxml2-git8123c4f6_debug\win32\../include/libxml/xmlversion.h(105):
error: expected an expression
  #if @WITH_THREAD_ALLOC@
      ^
Z:\...\libxml2-git8123c4f6_debug\win32\../include/libxml/xmlversion.h(105):
error: unrecognized token
  #if @WITH_THREAD_ALLOC@
                        ^
NMAKE : fatal error U1077: 'icl' : return code '0x2'
Stop.
diff --git a/win32/configure.js b/win32/configure.js
index 11d2898..edd943a 100644
--- a/win32/configure.js
+++ b/win32/configure.js
@@ -305,6 +305,8 @@
 			of.WriteLine(s.replace(/\@WITH_TRIO\@/, withTrio? "1" : "0"));
 		} else if (s.search(/\@WITH_THREADS\@/) != -1) {
 			of.WriteLine(s.replace(/\@WITH_THREADS\@/, withThreads == "no"? "0" : "1"));
+		} else if (s.search(/\@WITH_THREAD_ALLOC\@/) != -1) {
+			of.WriteLine(s.replace(/\@WITH_THREAD_ALLOC\@/, "0"));
 		} else if (s.search(/\@WITH_FTP\@/) != -1) {
 			of.WriteLine(s.replace(/\@WITH_FTP\@/, withFtp? "1" : "0"));
 		} else if (s.search(/\@WITH_HTTP\@/) != -1) {