The do_deploy task depends on xen-devicetree:do_deploy in order to
include the generated xen dtbs in the firmware image.
To avoid dependency loop between firmware-image-juno:do_install,
xen:do_deploy and xen-devicetree:do_deploy when
INITRAMFS_IMAGE_BUNDLE = "1", we need to handle the xen and
xen-devicetree binaries copying in the do_deploy task.

Also Use OVERRIDES to minimize the usage of
"@bb.utils.contains('DISTRO_FEATURES', 'xen', ..."

Change-Id: I8da476435de73445fb6d895ec418d85861b8c46c
Issue-Id: SCM-990
Signed-off-by: Diego Sueiro <diego.sueiro@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>