clk: X1000: Add support for the X1000 v2.

[Zhou Yanjie]

v1->v2:use BIT() macro instead left shift, add a call of
"ingenic_cgu_register_syscore_ops()", replace "CLK_OF_DECLARE"
with a "CLK_OF_DECLARE_DRIVER".

clk: X1000: Add support for the X1000.

[Zhou Yanjie]

1.Add the clock bindings for X1000 from Ingenic.
2.Add support for the clocks provided by the CGU in the
  Ingenic X1000 SoC.