Add smartmontools package to DIB image

This package includes smartctl, which is necessary for ATA secure erase
disk cleaning.

Without this package, IPA will fall back to shredding ATA devices, and
you will lose hours of your life. Worse, until
https://review.opendev.org/c/openstack/ironic-python-agent/+/847591, the
lack of smartctl was silently ignored.

Change-Id: I6952b833e0be4a47e45e9c4d4459956093628b6a
(cherry picked from commit 57f50f7e10)

dib/ironic-python-agent-ramdisk/package-installs.yaml

@@ -27,6 +27,8 @@ e2fsprogs:
 nvme-cli:
 # This provides iscsistart which is required for iBFT support
 open-iscsi:
+# smartctl is required for ATA secure erase.
+smartmontools:
 
 libffi-dev:
     build-only: true