mips: ingenic: Do not manually reference the CPU clock

mips: ingenic: Do not manually reference the CPU clock

It isn't necessary to manually walk the device tree and enable
the CPU clock anymore. The CPU and other necessary clocks are
now flagged as critical in the clock driver, which accomplishes
the same thing in a more declarative fashion.

Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20220428164454.17908-4-aidanmacdonald.0x0@gmail.com
Tested-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com> # On X1000 and X1830
Signed-off-by: Stephen Boyd <sboyd@kernel.org>