machine type 9006-12P (power9) comes with it's disks attached to
an aacraid controller.

please compile this driver on ppc64le as well:

commit 56dd6875f93b5a22b71d7fd61b8e677e3a02022c
Author: Ruediger Oertel <ro@suse.de>
Date:   Wed Oct 31 17:58:05 2018 +0100

    enable AACRAID on ppc64le for new boxes

diff --git a/config/ppc64le/default b/config/ppc64le/default
index 7812132c18..9c3b865306 100644
--- a/config/ppc64le/default
+++ b/config/ppc64le/default
@@ -2059,7 +2059,7 @@ CONFIG_CXLFLASH=m
 # CONFIG_SCSI_3W_9XXX is not set
 CONFIG_SCSI_3W_SAS=m
 # CONFIG_SCSI_ACARD is not set
-# CONFIG_SCSI_AACRAID is not set
+CONFIG_SCSI_AACRAID=m
 # CONFIG_SCSI_AIC7XXX is not set
 # CONFIG_SCSI_AIC79XX is not set
 CONFIG_SCSI_AIC94XX=m