Warn when smartctl not found

Currently, if smartctl is not found by IPA, it will silently skip ATA
secure erase and proceed to shred (if enabled). This is supposedly for
backwards compatibility, but is quite hard to diagnose.

This change adds a warning message to make it more obvious what is
happening.

TrivialFix

Change-Id: I03a381e99de79f201ec7e9a388777c3d48457e93
(cherry picked from commit b68fa6b)

Author: markgoddard

ironic_python_agent/hardware.py

@@ -1688,10 +1688,11 @@ def _smartctl_security_check(self, block_device):
                         'ATA commands via the `smartctl` utility with device '
                         '%s do not succeed.', block_device.name)
             return False
-        except OSError:
+        except OSError as e:
             # Processutils can raise OSError if a path is not found,
             # and it is okay that we tollerate that since it was the
             # prior behavior.
+            LOG.warning('Unable to execute `smartctl` utility: %s', e)
             return True
 
     def _ata_erase(self, block_device):