* config.guess (CRAY*X-MP:*:*:*, CRAY-2:*:*:*): Remove, as we know
they no longer exist in the field.
* config.sub (cray2, xmp): Likewise.
(cray, ymp, [cj]90-cray): basic_machine is now j90-cray.
(sv1-cray, cray-t3e, cray-t3d, cray-t90): New basic machine patterns.