Change license of filenames.h to LGPL

[Eli Zaretskii]

> From: Florian Weimer <fw@deneb.enyo.de>
> Cc: DJ Delorie <dj@redhat.com>,  gcc-patches@gcc.gnu.org,  sezeroz@gmail.com
> Date: Wed, 28 Sep 2016 16:43:53 +0200
> 
> * Eli Zaretskii:
> 
> > If my arithmetics is correct, about 70% of its files is LGPL, the
> > rest GPL.  Which doesn't keep many GNU projects under GPL from using
> > Gnulib.
> 
> Sorry, I don't understand.  Surely anything released under the LGPL by
> the FSF can be upgraded to the current GPLv3?  First upgrade to the
> latest LGPL, then switch over to the GPLv3?
> 
> (I assume that the FSF releases their works under the “any later
> version” regime.)

The above was in response to DJ's questions up-thread:

> > Because Ozkan wants to use it in an otherwise LGPL package.
> 
> But then the implementation would need relicensing as well, wouldn't
> it?
> 
> Having both under different licenses is just confusing.

Did I misunderstand the question?