ISO image from iso element fails to boot if baremetal has /vmlinuz on a partition

[Ramakrishnan G (rameshg87)]

Currently the iso element sets its grub root by searching for vmlinuz. When the deployed image on the disk contains /vmlinuz file, grub chooses that as the root partition which causes grub to fail to read the configuration file.

(hd0) -> disk on the baremetal node
   (hd0, 1) -> partition on the baremetal node

(cd0) -> virtual media attached on baremetal node.

When (hd0,1) has a file named /vmlinuz, currently created ISO image in grub chooses (hd0,1) as the root partition and fails to boot.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/130606

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/130606
Committed: https://git.openstack.org/cgit/openstack/diskimage-builder/commit/?id=8c9ee78ab584224e89c0a03da005c4e3bcf19ff1
Submitter: Jenkins
Branch: master

commit 8c9ee78ab584224e89c0a03da005c4e3bcf19ff1
Author: Ramakrishnan G <email address hidden>
Date: Thu Oct 23 22:24:18 2014 +0530

    iso element to use 'search --label' for grub

    Current iso element uses 'search --file' to find the
    grub root. This is a wrong approach as it may find
    some other partition containing /vmlinuz. Instead modify
    it to search for grub root by the label of ISO image.

    Closes-Bug: 1384826
    Change-Id: Id4217be3420597bed2f80a96788928259ec91582