4th attempt to silence coverity about the use of fpos_t

git-svn-id: http://root.cern.ch/svn/root/trunk@41695 27541ba8-7e3a-0410-8455-c3a389f83636

cint/cint/src/macro.cxx

@@ -732,6 +732,8 @@ G__value G__execfuncmacro(const char* item, int* done)
    fpos_t call_pos;
    if (G__ifile.fp) {
       fgetpos(G__ifile.fp, &call_pos);
+   } else {
+      memset(&call_pos,0,sizeof(fpos_t));
    }
    //
    //  Search for translated macro function.