boards: arm: Configure sensor devicetree aliases on tdk_robokit1

Configures magnetometer, accelerometer, and die temperature devicetree
aliases on the tdk_robokit1 board to enable generic sensor sample
applications (magn_polling, accel_polling, die_temp_polling) on this
board.

Signed-off-by: Maureen Helm <maureen.helm@intel.com>