configure --without-dmalloc doesn't work.

Imported from http://bugzilla.roxen.com/bugzilla/show_bug.cgi?id=2363

Reported by @grubba

From: John W Pierce <jwp@ucsd.edu>
To: "pike@roxen.com" <pike@roxen.com>
Date: Wed, 3 Oct 2001 14:09:57 -0700
Subject: RE: v7.3 - verbose_debug_exit is set  unconditionally in
pike_memory.c

From: Henrik Grubbström [mailto:grubba@roxen.com]

Hmm, looks like you've compiled with dmalloc...

Below is the configuration used.

configure --prefix=/usr/local \
    --with-include-path="$CPPFLAGS" \
    --with-double-precision \
    --with-int-int \
    --with-oob \
    --with-security \
    --with-shared-nodes \
    --without-cdebug \
    --without-debug \
    --without-dmalloc \
    --without-dmalloc-malloc \
    --without-rtldebug \
    --without-thread-trace

You are correct, however, that DEBUG_MALLOC is defined in machine.h after configuration, even though should explicitly prevent that.