dts: Reduce include paths for building dts
dts: Reduce include paths for building dts

Drop a few paths from when we preprocess the dts.  This is to reduce
creep of where #defines might get resolved from.

Signed-off-by: Kumar Gala <a5e5248af4cd4f0ed8c515f61d40a6e2db46a66e@linaro.org>

ldts/zephyr,ldts/zephyr,ldts/zephyr,nashif/zephyr,explora26/zephyr,punitvara/zephyr,GiulianoFranchetto/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,Vudentz/zephyr,galak/zephyr,punitvara/zephyr,Vudentz/zephyr,galak/zephyr,Vudentz/zephyr,explora26/zephyr,punitvara/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,explora26/zephyr,explora26/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,Vudentz/zephyr,ldts/zephyr,finikorg/zephyr,Vudentz/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,explora26/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,punitvara/zephyr,punitvara/zephyr,zephyrproject-rtos/zephyr,ldts/zephyr,Vudentz/zephyr,finikorg/zephyr