Fixed curl-config --features to not display libz when it wasn't used

due to a missing header file.

CHANGES

@@ -6,6 +6,10 @@
 
                                   Changelog
 
+Dan F (1 Nov 2007)
+- Fixed curl-config --features to not display libz when it wasn't used
+  due to a missing header file.
+
 Dan F (31 October 2007)
 - Fixed the output of curl-config --protocols which showed SCP and SFTP
   always, except when --without-libssh2 was given

RELEASE-NOTES

@@ -15,7 +15,7 @@ This release includes the following changes:
 This release includes the following bugfixes:
 
  o curl-config --features and --protocols show the correct output when built
-   with NSS, and also when SCP and SFTP are not available
+   with NSS, and also when SCP, SFTP and libz are not available
 
 This release includes the following known bugs:
 

configure.ac

@@ -1292,6 +1292,7 @@ else
   if test "$HAVE_LIBZ" = "1" && test "$HAVE_ZLIB_H" != "1"
   then
     AC_MSG_WARN([configure found only the libz lib, not the header file!])
+    HAVE_LIBZ=""
   elif test "$HAVE_LIBZ" != "1" && test "$HAVE_ZLIB_H" = "1"
   then
     AC_MSG_WARN([configure found only the libz header file, not the lib!])