crypto: ingenic - Add hardware RNG for Ingenic JZ4780 and X1000

Add JZ4780 SoC and X1000 SoC random number generator driver,
based on PrasannaKumar Muralidharan's JZ4780 RNG driver.

Tested-by: 周正 (Zhou Zheng) <sernia.zhou@foxmail.com>
Tested-by: Mathieu Malaterre <malat@debian.org>
Suggested-by: Jeffrey Walton <noloader@gmail.com>
Signed-off-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>