[PATCH v3] doc: add removal note for power empty poll API

[Thomas Monjalon]

07/10/2022 15:40, Reshma Pattan:
> --- a/doc/guides/prog_guide/power_man.rst
> +++ b/doc/guides/prog_guide/power_man.rst
> @@ -192,6 +192,14 @@ User Cases
>  ----------
>  The mechanism can applied to any device which is based on polling. e.g. NIC, FPGA.
>  
> +
> +Removal Note
> +------------
> +
> +The experimental empty poll APIs will be removed from the library in a future
> +DPDK release.

After more thoughts, I think it would be better highlighted if moved
at the beginning of the section "Empty Poll API".
It could a note block or a warning.

Also, could we explain how it is replaced?