of: property: define of_property_read_u{8,16,32,64}_array() unconditionally

We can get rid of all the empty stubs because all these functions call
of_property_read_variable_u{8,16,32,64}_array() which already have an
empty stub if CONFIG_OF is not defined.

Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220118173504.2867523-3-michael@walle.cc