apr-util/misc/apr_thread_pool.c compile failure in VC6

[Curt Arnold]

apr_thread_pool.c did not appear in the VC6 project in 1.2.8, but has  
been added in the SVN HEAD and it fails to compile under VC6 in debug  
mode due to a C++ style variable declaration.  The following change  
fixes the compile error.

Index: apr_thread_pool.c
===================================================================
--- apr_thread_pool.c   (revision 534087)
+++ apr_thread_pool.c   (working copy)
@@ -595,6 +595,7 @@

static void wait_on_busy_threads(apr_thread_pool_t * me, void *owner)
{
+    apr_os_thread_t *os_thread;
     struct apr_thread_list_elt *elt;
     apr_thread_mutex_lock(me->lock);
     elt = APR_RING_FIRST(me->busy_thds);
@@ -605,7 +606,6 @@
         }
#ifndef NDEBUG
         /* make sure the thread is not the one calling tasks_cancel */
-        apr_os_thread_t *os_thread;
         apr_os_thread_get(&os_thread, elt->thd);
#ifdef WIN32
         /* hack for apr win32 bug */