[RFA] Make "bt N" print correct number of frames when using a frame filter

[Tom Tromey]

>>>>> "Pedro" == Pedro Alves <palves@redhat.com> writes:

Pedro> Can you expand on the need for the PRINT_MORE_FRAMES flag and
Pedro> having it based on from_tty?  I assume that your first made
Pedro> the printing unconditional, but then for some reason decided
Pedro> against it?

I think my reason was just to have it parallel the no-frame-filter code
in stack.c:

      /* If we've stopped before the end, mention that.  */
      if (fi && from_tty)
	printf_filtered (_("(More stack frames follow...)\n"));

I don't know why this code is conditional on from_tty, but that seemed
like a separate decision.

Tom