[Snek] [keith-packard/snek] 19fe82: Support ArduinoISP as programmer

[Eliot Blennerhassett]

  Branch: refs/heads/master
  Home:   https://github.com/keith-packard/snek
  Commit: 19fe827f38b98eab3e2bddf66537c5d3b34a368c
      https://github.com/keith-packard/snek/commit/19fe827f38b98eab3e2bddf66537c5d3b34a368c
  Author: Eliot Blennerhassett <eliot at blennerhassett.gen.nz>
  Date:   2019-10-22 (Tue, 22 Oct 2019)

  Changed paths:
    M ports/duemilanove/snek-duemilanove-install.in

  Log Message:
  -----------
  Support ArduinoISP as programmer

Allow setting port for any avrdude programmer

Signed-off-by: Eliot Blennerhassett <eliot at blennerhassett.gen.nz>