Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

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

Merge from vendor branch importing dtc git rev 6a15eb2350426d285130e4c9d84c0bdb6575547a

Merge DTC-d75b33af.

This is a split merge because of non-uniform licensing of the DTC package
contents and the way these components will be used in the FreeBSD environment.

The original DTC package is composed of the following two major pieces:

1. sys/contrib/libfdt (BSD [dual] license)
2. contrib/dtc (GPLv2)

The libfdt component is going to be shared in all aspects of the environment:
- /boot/loader
- kernel
- dtc (the device tree compiler proper, userspace tool)

Initial import of the Device Tree Compiler (DTC) package v1.2.0.

Obtained from: git://git.jdl.com/software/dtc.git