MIPS: X1830: Respect cell count of common properties.

If N fields of X cells should be provided, then that's what the
devicetree should represent, instead of having one single field of
(N * X) cells.

Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>