Protect included headers with the proper autoconf macros

[Jacek Caban]

Francois Gouget wrote:

> On Wed, 10 Aug 2005, Jacek Caban wrote:
> [...]
>
>> But it won't change anything as if HAVE_LIBXML2 is defined
>> then HAVE_LIBXML_PARSER_H is defined too, so
>> #ifdef HAVE_LIBXML_PARSER_H will be always true here.
>
>
> Yes but if you remove the #ifdef HAVE_LIBXML_PARSER_H check 
> winapi_check will rightly complain that the include is unprotected 
> because it, nor the casual reader, will know all the complex relations 
> between HAVE_LIBXML_PARSER_H and HAVE_LIBXML2.
>
Ah, I see. So Mike's solution is good for this.

Jacek