Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC 264230: Move dts files accidentally placed in arm dir to powerpc dir.

These were bogusly placed in the arm directory. Move them to their
proper location in powerpc directory.

Integrate device-tree upstream files into the build process:
(1) Invoke cpp to bring in files via #include (although the old
/include/ stuff is supported still).
(2) bring in files from either vendor tree or freebsd-custom files
when building.
(3) move all dts* files from sys/boot/fdt/dts to
sys/boot/fdt/dts/${MACHINE} as appropriate.
(4) encode all the magic to do the build in sys/tools/fdt/make_dtb.sh
so that the different places in the tree use the exact same logic.
(5) switch back to gpl dtc by default. the bsdl one in the tree has
significant issues not easily addressed by those unfamiliar with
the code.

Import DTS files for the upcoming DPAA QorIQ (PowerPC) support.

- P2041RDB
- P3041DS
- P5020DS

Obtained from: Freescale