[Bug testsuite/82920] cet test failures on darwin

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82920

--- Comment #4 from Iain Sandoe <iains at gcc dot gnu.org> ---
It might be better to move all the CET tests into a separate directory with a
.exp file that tests for compile-time (and runtime) support, so that as
hardware becomes available - and assembler support, things just start to work
without further intervention.

An alternative might be to include 

/* { dg-require-effective-target cet } */

in every test.