Several devices can be attached to memory controllers (or memory-mapped
buses), thus they can come with additional controller-specific
properties, e.g. devices wired under Intel IXP4XX bus: cfi-flash,
intel,ixp4xx-compact-flash, NS8250 serial and MAX6369 watchdog.

Referencing Memory Controller or IXP4XX bus peripheral properties fixes
few dtbs_check warnings like:

  intel-ixp42x-gateworks-gw2348.dtb: ide@1,0: Unevaluated properties are not allowed
    ('intel,ixp4xx-eb-ahb-split-transfers', 'intel,ixp4xx-eb-byte-access', ... ' were unexpected)
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20230206092624.22922-3-krzysztof.kozlowski@linaro.orgSigned-off-by: Rob Herring <robh@kernel.org>