Changes to aerocore for upstream Nuttx

nuttx-configs/aerocore/include/board.h

nuttx-configs/aerocore/nsh/Make.defs

nuttx-configs/aerocore/nsh/appconfig

nuttx-configs/aerocore/nsh/defconfig

nuttx-configs/aerocore/nsh/setenv.sh

nuttx-configs/aerocore/scripts/ld.script

nuttx-configs/aerocore/src/Makefile

src/drivers/boards/aerocore/CMakeLists.txt

src/drivers/boards/aerocore/aerocore_init.c

src/drivers/boards/aerocore/aerocore_led.c

src/drivers/boards/aerocore/aerocore_spi.c

src/drivers/boards/aerocore/board_config.h