This patch converts to the new tree checking framework those checks
which verify that certain properties (#address-cells and #size-cells)
are exactly one cell in size, when present.
We also drop the old-style check for "linux,phandle" being one cell,
since that is already implied in the the existing new-style checks on
the linux,phandle property.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>