linux-user: Remove support for CRIS target

linux-user: Remove support for CRIS target

As per the deprecation notice in commit c7bbef4023:

  The CRIS architecture was pulled from Linux in 4.17 and
  the compiler is no longer packaged in any distro making
  it harder to run the `check-tcg` tests. Unless we can
  improve the testing situation there is a chance the code
  will bitrot without anyone noticing.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Message-ID: <20240904143603.52934-5-philmd@linaro.org>