dt-bindings: mfd: allwinner: prcm: Simplify conditional schemas

dt-bindings: mfd: allwinner: prcm: Simplify conditional schemas

There's no need for 'additionalProperties' in the if/then schema as there's
already 'unevaluatedProperties' in the parent schema. With
'additionalProperties' dropped, 'compatible' and 'phandle' don't need
to be listed in the conditional schemas as 'compatible' is already in
the main section and 'phandle' will be implicitly added.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230726033554.174365-1-robh@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>