[PATCH v2 18/31] clk: mediatek: Implement mtk_clk_unregister_composites() API

[Miles Chen]

> mtk_clk_register_composites(), as the name suggests, is used to register
> a given list of composite clks. However it is lacking a counterpart
> unregister API.
> 
> Implement said unregister API so that the various clock platform drivers
> can utilize it to do proper unregistration, cleanup and removal.
> 
> In the header file, the register function's declaration is also
> reformatted to fit code style guidelines.
> 
> Signed-off-by: Chen-Yu Tsai <wenst at chromium.org>

Reviewed-by: Miles Chen <miles.chen at mediatek.com>