boards: mimxrt1060_evk: Add Arduino I2C support

When ever a Ardunio UNO R3 compatible shield will be used
together with the NXP MIMXRT1060-EVK board Zephyr runs into
an DTS parse error because of missing label 'arduino_i2c'.

On NXP MIMXRT1060-EVK pin A4 (SDA) and A5 (SCL) will be shared
with multiple on-board components: audio codec, sensors, CSI and
LCD and M.2(E) header. Pin D14 (SDA) and D15 (SCL) are connected
in parallel, but can be opened optionally.

Signed-off-by: Stephan Linz <linz@li-pro.net>