[patch] README: remove references to deleted remote-*.c

[Andrew Cagney]

> Ah, you are referring to the bug reporting stuff, rather than
> the obsolete remote-*.c stuff.  I was a little mystified.
> 
> By the way, what happens to bugs reported to the mailing lists?
> Is anyone entering them into Gnats?

They dried up!  The power of documentation!

All N places which mention bug reports how recommend 
http://www.gnu.org/software/gdb/bugs/ in preference to the bug-gdb@ 
mailing list.

Andrew