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

[Michael Elizabeth Chastain]

Andrew C writes:
> Michael, check the bug database for some additional state on this.  The 
> `correct fix' involves an addition to the documentation.

I did some keyword searches and then read through the 574 open synopses.
The closest I found was:

  PR gdb/685  remote-utils and remote-array obsolete
  PR gdb/118  update remote protocol doco

These don't seem very close to me.

Would you like me to revert the patch?  I thought it was obvious,
but maybe it's not.

Michael C