fix: Use distro agnostic commands in logdump.sh
fix: Use distro agnostic commands in logdump.sh

The command 'lsb_release' is not available in RHEL. Saving the contents
of '/etc/os-release' provides the same information and works in both
Ubuntu and RHEL.

Change-Id: Iba728a2904456607fd4cb5589b5e05f5ee8162d4

open-power-ref-design-toolkit/cluster-genesis,open-power-ref-design-toolkit/cluster-genesis