configure.ac: don't overwrite NO_EXPAT option

Even if 'configure --with-expat=no' was run, expat support is used,
because library detection overwrites it. Avoid this overwrite.
Configure should obey what the user has specified.

Signed-off-by: Andreas Herrmann <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: Andreas Herrmann

configure.ac

@@ -581,6 +581,8 @@ fi
 # Define NO_EXPAT if you do not have expat installed.  git-http-push is
 # not built, and you cannot push using http:// and https:// transports.
 
+if test -z "$NO_EXPAT"; then
+
 GIT_STASH_FLAGS($EXPATDIR)
 
 AC_CHECK_LIB([expat], [XML_ParserCreate],
@@ -589,6 +591,8 @@ AC_CHECK_LIB([expat], [XML_ParserCreate],
 
 GIT_UNSTASH_FLAGS($EXPATDIR)
 
+fi
+
 GIT_CONF_SUBST([NO_EXPAT])
 
 #