The btt3 device' HW revisions from 0 to 2 use imx287 SoC and are to
some extend similar to already upstreamed XEA devices, hence are
using common imx28-lwe.dtsi file.
New, imx28-btt3.dtsi has been added to embrace common DTS
properties for different HW revisions for this device.
As a result - changes introduced in imx28-btt3-[012].dts are
minimal.
Signed-off-by: Lukasz Majewski <lukma@xxxxxxx>