of/unittest: add const where needed
of/unittest: add const where needed

Fix warnings pointed out by checkpatch.

No bugs fixed, but the test code should be a good example of how to use
the devicetree API.

Signed-off-by: Frank Rowand <964289eda363137c5cb6fd2bdcdba711c4b6176d@sonymobile.com>
Signed-off-by: Grant Likely <9069e6f5a2b566e2674a0ba1e2bf39c12c195fad@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs