[PATCH, various] Add "pdf" target to all relevant GCC makefiles.

[Brooks Moses]

DJ Delorie wrote:
> Don't forget that the toplevel is shared with gdb, binutils, newlib,
> cygwin, etc.  You went to great lengths to add dummy pdf targets in
> all the gcc directories, but won't this break those other projects?
> 
> I'm assuming your answer will be "use make -k for now" which is
> probably sufficient, but I didn't want this to pass without
> consideration.

It shouldn't break them, so far as I understand things -- according to 
the GNU Coding Standards, the "pdf" target should not be a dependency of 
the "all" target, but must be manually invoked.  That's certainly the 
case here, and thus "make all" isn't affected at all by these changes.

However, yes, the top-level "make pdf" target, which didn't previously 
exist, may be broken on those other projects.  (Or it may not -- 
anything which builds its Makefile.in with automake already gets an 
empty "pdf" target.)  There, my recommendation would be more one of 
"Don't run 'make pdf'" rather than "use 'make -k pdf'", though, since 
without targets it won't do anything useful!

> The patch is otherwise technically OK, assuming Mark allows it in
> stage 3.

Thanks.  So, to be clear: If Mark allows it, this should cover all of 
the approving I need in order to commit the whole patch, yes?

- Brooks