[PATCH]selftests/powerpc: skip tests for unavailable mitigations.

[Russell Currey]

On Mon, 2021-12-13 at 22:12 +0530, Sachin Sant wrote:
> Mitigation patching test iterates over a set of mitigations
> irrespective
> of whether a certain mitigation is supported/available in the kernel.
> This causes following messages on a kernel where some mitigations
> are unavailable:
> 
>   Spawned threads enabling/disabling mitigations ...
>   cat: entry_flush: No such file or directory
>   cat: uaccess_flush: No such file or directory
>   Waiting for timeout ...
>   OK
> 
> This patch adds a check for available mitigations in the kernel.
> 
> Reported-by: Nageswara R Sastry <rnsastry at linux.ibm.com>
> Signed-off-by: Sachin Sant <sachinp at linux.vnet.ibm.com>

Reviewed-by: Russell Currey <ruscur at russell.cc>