clk: Extend clock control with an optional data field

Some systems require more than a single ID to identify and configure any
clock provider. For those scenarios add an optional data field to the
clock control structure.

Reviewed-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>