Comment 4 for bug 1927515

Reviewed: https://review.opendev.org/c/starlingx/utilities/+/790094
Committed: https://opendev.org/starlingx/utilities/commit/6045b1b8a0d8ed6a94d06cdfc994bf1a5fa9dbb5
Submitter: "Zuul (22348)"
Branch: master

commit 6045b1b8a0d8ed6a94d06cdfc994bf1a5fa9dbb5
Author: Jim Gauld <email address hidden>
Date: Thu May 6 11:58:34 2021 -0400

    Provide utility script is-rootdisk-device.sh

    This provides a utility script to determine which disk contains the root
    filesystem. This can also be used as a helper function for io-scheduler
    udev rules that require specific configuration for root disk.

    Example usage:
    /usr/local/bin/is-rootdisk-device.sh
    ROOTDISK_DEVICE=sda

    /usr/local/bin/is-rootdisk-device.sh /dev/sda
    ROOTDISK_DEVICE=sda

    /usr/local/bin/is-rootdisk-device.sh /dev/sdb
    (i.e., no output)

    Partial-Bug: 1927515
    Signed-off-by: Jim Gauld <email address hidden>
    Change-Id: Ib0d4a161a407b08d294c5ff9aa0b7590961e18c9