Changed code to avoid a compiler warning in mingw

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%402919

dlib/server/server_kernel_1.h

@@ -449,7 +449,7 @@ namespace dlib
 
 
             // make a param structure
-            param* temp;
+            param* temp = 0;
             try{
             temp = new param (
                             *this,