Current makefiles stupidly omit `-lz' when building `mkromfs'.

--- gnu-ghostscript-8.64.0/base/unix-aux.mak	2008-05-04 16:34:47.000000000 +0200
+++ gnu-ghostscript-8.64.0/base/unix-aux.mak	2008-07-17 17:58:20.000000000 +0200
@@ -97,7 +97,7 @@ MKROMFS_OBJS= $(MKROMFS_ZLIB_OBJS) $(GLO
 endif
 
 $(MKROMFS_XE): $(GLSRC)mkromfs.c $(MKROMFS_COMMON_DEPS) $(MKROMFS_OBJS)
-	$(CCAUX) $(GENOPT) $(CFLAGS) $(I_)$(GLSRCDIR)$(_I) $(I_)$(GLOBJ)$(_I) $(I_)$(ZSRCDIR)$(_I) $(GLSRC)mkromfs.c $(O_)$(MKROMFS_XE) $(MKROMFS_OBJS) -lm $(EXTRALIBS)
+	$(CCAUX) $(GENOPT) $(CFLAGS) $(I_)$(GLSRCDIR)$(_I) $(I_)$(GLOBJ)$(_I) $(I_)$(ZSRCDIR)$(_I) $(GLSRC)mkromfs.c $(O_)$(MKROMFS_XE) $(MKROMFS_OBJS) -lm $(EXTRALIBS) -lz
 
 # Query the environment to construct gconfig_.h.
 # The "else true;" is required because Ultrix's implementation of sh -e