MIPS: Ingenic: Add MAC syscon nodes for Ingenic SoCs.

Add MAC syscon nodes for X1000 SoC and X1830 SoC from Ingenic.

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>