[PATCH] clk: ux500: Drop AB8540/9540 support

[Stephen Boyd]

Quoting Linus Walleij (2018-03-22 03:16:18)
> The AB8540 was an evolved version of the AB8500, but it was never
> mass produced or put into products, only reference designs exist.
> The upstream support was never completed and it is unlikely that
> this will happen so drop the support for now to simplify
> maintenance of the AB8500.
> 
> Cc: Ulf Hansson <ulf.hansson at linaro.org>
> Cc: Loic Pallardy <loic.pallardy at st.com>
> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
> ---

Applied to clk-next