dafdac6731
Use all the disks except the one for rootfs for RAID0 which stores
scylla data. If only one disk is available warn the user since currently
our AMI's rootfs is not XFS.
[fedora@ip-172-31-39-189 ~]$ cat WARN.TXT
WARN: Scylla is not using XFS to store data. Performance will suffer.
Tested on AWS with 1 disk, 2 disks, 7 disk case.
(cherry picked from commit 49d6cba471)