Eliminate use of mktemp in Makefile (not always available).

Makefile.in

@@ -83,7 +83,7 @@ check: test
 test: all teststatic testshared
 
 teststatic: static
-	@TMPST=`mktemp fooXXXXXX`; \
+	@TMPST=tmpst_$$; \
 	if echo hello world | ./minigzip | ./minigzip -d && ./example $$TMPST ; then \
 	  echo '		*** zlib test OK ***'; \
 	else \
@@ -96,7 +96,7 @@ testshared: shared
 	LD_LIBRARYN32_PATH=`pwd`:$(LD_LIBRARYN32_PATH) ; export LD_LIBRARYN32_PATH; \
 	DYLD_LIBRARY_PATH=`pwd`:$(DYLD_LIBRARY_PATH) ; export DYLD_LIBRARY_PATH; \
 	SHLIB_PATH=`pwd`:$(SHLIB_PATH) ; export SHLIB_PATH; \
-	TMPSH=`mktemp fooXXXXXX`; \
+	TMPSH=tmpsh_$$; \
 	if echo hello world | ./minigzipsh | ./minigzipsh -d && ./examplesh $$TMPSH; then \
 	  echo '		*** zlib shared test OK ***'; \
 	else \
@@ -105,7 +105,7 @@ testshared: shared
 	rm -f $$TMPSH
 
 test64: all64
-	@TMP64=`mktemp fooXXXXXX`; \
+	@TMP64=tmp64_$$; \
 	if echo hello world | ./minigzip64 | ./minigzip64 -d && ./example64 $$TMP64; then \
 	  echo '		*** zlib 64-bit test OK ***'; \
 	else \
@@ -230,7 +230,7 @@ zlib.3.pdf: zlib.3
 	groff -mandoc -f H -T ps zlib.3 | ps2pdf - zlib.3.pdf
 
 zconf.h.cmakein: zconf.h.in
-	-@ TEMPFILE=`mktemp __XXXXXX`; \
+	-@ TEMPFILE=zconfh_$$; \
 	echo "/#define ZCONF_H/ a\\\\\n#cmakedefine Z_PREFIX\\\\\n#cmakedefine Z_HAVE_UNISTD_H\n" >> $$TEMPFILE &&\
 	sed -f $$TEMPFILE zconf.h.in > zconf.h.cmakein &&\
 	touch -r zconf.h.in zconf.h.cmakein &&\