samples/drivers: led_pca9633: Replace target stm32373c_eval

Pinctrl is missing in i2c1 device description on stm32373c_eval
ovderlay file, besides using I2C1 this board (as mentioned in readme)
requires to remove 2 resistors on the board.

Make it simple and instead use a board with arduino_i2c port
available.

Signed-off-by: Erwan Gouriou <erwan.gouriou@linaro.org>