dtc: Add basic testcases for dtc

[Jon Loeliger]

So, like, the other day David Gibson mumbled:
> This patch adds a handful of simple testcases for dtc.  It adds a dts
> file which should generate the same sample tree as is used for the
> libfdt testcases, and tests invoking dtc on this dts, plus the
> standard batch of libfdt cases on the resulting dtb, which effectively
> checks that the dtb is correct.
> 
> Because the test framework assumes each testcase is an executable with
> the right output conventions, we use a little shell script, dtc.sh, as
> a wrapper around dtc itself.  It simply invokes dtc and returns a PASS
> or FAIL depending on whether dtc returned an error.
> 
> It's not much, but it's a start.
> 
> Signed-off-by: David Gibson <david at gibson.dropbear.id.au>


Applied.

> NB: Jon, you won't be able to simply git-applymbox this and have it
> work.  You'll need to manually add execute permission to tests/dtc.sh
> before git commiting it, since I can't encode the permissions in a
> patch.  Sorry for the inconvenience, but it didn't really seem worth
> setting up my own git to pull from just for that.

No problem.  Too bad you can't just use git, though... :-)

jdl