Move vTaskPayload from board specific directory to a generic implementation in modules/

The is a lot of duplicated code on [port/board/afc-bpm/v3_1/payload.c](https://github.com/lnls-dig/openMMC/blob/eddf4fb4860ad58d5c8e150b3c99a8b379dd29fa/port/board/afc-bpm/v3_1/payload.c), [port/board/afc-fofb-ctrl/v3_1/payload.c](https://github.com/lnls-dig/openMMC/blob/eddf4fb4860ad58d5c8e150b3c99a8b379dd29fa/port/board/afc-fofb-ctrl/v3_1/payload.c), [port/board/afc-timing/payload.c](https://github.com/lnls-dig/openMMC/blob/eddf4fb4860ad58d5c8e150b3c99a8b379dd29fa/port/board/afc-timing/payload.c) and [port/board/afc-v4/payload.c](https://github.com/lnls-dig/openMMC/blob/eddf4fb4860ad58d5c8e150b3c99a8b379dd29fa/port/board/afc-v4/payload.c). This can be unified in a single generic implementation of vTaskPayload that calls board specific functions for managing the payload power.

Compare the duplicated implementations in port/board/afc-bpm/v3_1/payload.c, port/board/afc-fofb-ctrl/v3_1/payload.c, port/board/afc-timing/payload.c, and port/board/afc-v4/payload.c. Identify the shared vTaskPayload logic and the board-specific payload power functions, then inspect modules/ for the appropriate generic implementation location. Done means vTaskPayload is unified in modules/ while board-specific power management remains available through board functions.

Written by the indexing model from the issue text.