oeqa: Use the linux terminal utilities in the virtualization suite

The virtualization test suite inherits from meta-arm and was
overriding the run command utility to run and check commands on DomU.
This resulted in a transient error in reading back the echo of the
command since this is sensitive to timing. The utility also had to
filter out messages from Xen hypervisor which are observed on the
telnet session.

To fix both issues, use the Linux terminal utilities, which SSH to
Dom0 and mean that the Xen hypervisor messages are not seen. This
also increases code commonality.

Signed-off-by: Debbie Martin <Debbie.Martin@arm.com>