clk: spacemit: set up reset auxiliary devices

clk: spacemit: set up reset auxiliary devices

Add a new reset_name field to the spacemit_ccu_data structure.  If it is
non-null, the CCU implements a reset controller, and the name will be
used in the name for the auxiliary device that implements it.

Define a new type to hold an auxiliary device as well as the regmap
pointer that will be needed by CCU reset controllers.  Set up code to
initialize and add an auxiliary device for any CCU that implements reset
functionality.

Make it optional for a CCU to implement a clock controller.  This
doesn't apply to any of the existing CCUs but will for some new ones
that will be added soon.

Signed-off-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Haylen Chu <heylenay@4d2.org>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20250702113709.291748-4-elder@riscstar.com
Signed-off-by: Yixun Lan <dlan@gentoo.org>