boards: esp32: move board specific kconfig definitions

HEAP_MEM_POOL_ADD_SIZE_BOARD is not a zephyr-defined entry and
should be placed into Kconfig instead of Kconfig.defconfig.

This PR moves that entry for all ESP32-based boards accordingly.

Signed-off-by: Sylvio Alves <sylvio.alves@espressif.com>
76 files changed