[Snek] [keith-packard/snek] 0a22b9: Remove more references to updated boot loaders

[Keith Packard]

  Branch: refs/heads/main
  Home:   https://github.com/keith-packard/snek
  Commit: 0a22b965ff74881f2037182207cf2e91210048ed
      https://github.com/keith-packard/snek/commit/0a22b965ff74881f2037182207cf2e91210048ed
  Author: Keith Packard <keithp at keithp.com>
  Date:   2021-02-05 (Fri, 05 Feb 2021)

  Changed paths:
    M doc/snek.adoc
    M snek-install.defs

  Log Message:
  -----------
  Remove more references to updated boot loaders

Signed-off-by: Keith Packard <keithp at keithp.com>