Fix typos and heading
Fix typos and heading

Minor edits

Signed-off-by: Kanta Vekaria <ae794cff6c0c11be1be9c869e6aaf3ec0e3cf52e@linaro.org>
Signed-off-by: Grant Likely <9069e6f5a2b566e2674a0ba1e2bf39c12c195fad@linaro.org>

devicetree-org/devicetree-specification,kvekaria/devicetree-specification