arm: imx6q: pcm058: Convert pcm058 to use DM with DTs

Convert pcm058 support to use device trees and the driver model.
Add rudimentary boot scripts to the environment, expand README.

Signed-off-by: Niel Fourie <lusus@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index d839cb4..cee10f5 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -678,6 +678,7 @@
 	imx6q-nitrogen6x.dtb \
 	imx6q-novena.dtb \
 	imx6q-pico.dtb \
+	imx6q-phytec-mira-rdk-nand.dtb \
 	imx6q-sabreauto.dtb \
 	imx6q-sabrelite.dtb \
 	imx6q-sabresd.dtb \