MAINTAINERS: altx: move Jay Cliburn to CREDITS

MAINTAINERS: altx: move Jay Cliburn to CREDITS

Jay was not active in recent years and does not have plans
to return to work on ATLX drivers.

Subsystem ATLX ETHERNET DRIVERS
  Changes 20 / 116 (17%)
  Last activity: 2020-02-24
  Jay Cliburn <jcliburn@gmail.com>:
  Chris Snook <chris.snook@gmail.com>:
    Tags ea973742140b 2020-02-24 00:00:00 1
  Top reviewers:
    [4]: andrew@lunn.ch
    [2]: kuba@kernel.org
    [2]: o.rempel@pengutronix.de
  INACTIVE MAINTAINER Jay Cliburn <jcliburn@gmail.com>

Acked-by: Chris Snook <chris.snook@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>