selftests/powerpc: skip tests for unavailable mitigations.

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 <[email protected]>
Signed-off-by: Sachin Sant <[email protected]>
Tested-by: Nageswara R Sastry <[email protected]>
Reviewed-by: Russell Currey <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/163941374362.36967.18016981579099073379.sendpatchset@1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa

0 files changed, 0 insertions, 0 deletions