ARM: dts: vexpress: fix node name unit-address presence warnings

Commit b9937347 ("scripts/dtc: Update to upstream version 53bf130b1cdd")
added warnings on node name unit-address presence/absence mismatch in
the device trees.

This patch fixes those warning on all the vexpress platforms where
unit-address is present in node name while the reg/ranges property is
not present.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>