[jit] Drop libgccjit.pc

[David Malcolm]

On Mon, 2014-10-20 at 22:11 +0200, Basile Starynkevitch wrote:
> On Mon, 2014-10-20 at 13:54 -0400, David Malcolm wrote:
> > Committed to branch dmalcolm/jit:
> > 
> > pkg-config appears to be controversial, so don't provide a .pc file.
> 
> 
> I would put it under contrib/; it is controversial, but some would like
> to have it.

It was generated, via some Makefile.in and configure.ac hooks, so I
don't think putting it under contrib/ allows us to sidestep that.

(FWIW, I'm one of the ones who'd like to have a .pc file, but I'd rather
focus on getting the jit in before stage1 closes)

Thanks
Dave