This commit refactors the corediv clock driver so that it is capable
of handling various SOCs that have slightly different corediv clock
registers and capabilities.

It introduces a clk_corediv_soc_desc structure that encapsulates all
the SoC specific details.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>