MIPS: Ingenic: Refresh defconfig for Ingenic SoCs based boards.

1.Refresh defconfig of CI20 to support OTG and RNG.
2.Refresh defconfig of CU1000-Neo to support OTG/RNG/OST/SC16IS752.
3.Refresh defconfig of CU1830-Neo to support OTG/DTRNG/OST/SC16IS752.

Tested-by: 周正 (Zhou Zheng) <sernia.zhou@foxmail.com>
Tested by: H. Nikolaus Schaller <hns@goldelico.com> # CI20/jz4780
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>