Merge pull request #9426 from gschorcht/esp32

boards/common/esp32/Makefile

boards/common/esp32/Makefile.dep

boards/common/esp32/Makefile.features

boards/common/esp32/Makefile.include

boards/common/esp32/board_common.c

boards/common/esp32/doc.txt

boards/common/esp32/include/arduino_board_common.h

boards/common/esp32/include/board_common.h

boards/common/esp32/include/periph_conf_common.h

boards/esp32-mh-et-live-minikit/Makefile

boards/esp32-mh-et-live-minikit/Makefile.dep

boards/esp32-mh-et-live-minikit/Makefile.features

boards/esp32-mh-et-live-minikit/Makefile.include

boards/esp32-mh-et-live-minikit/doc.txt

boards/esp32-mh-et-live-minikit/include/arduino_board.h

boards/esp32-mh-et-live-minikit/include/arduino_pinmap.h

boards/esp32-mh-et-live-minikit/include/board.h

boards/esp32-mh-et-live-minikit/include/board_modules.h

boards/esp32-mh-et-live-minikit/include/gpio_params.h

boards/esp32-mh-et-live-minikit/include/periph_conf.h