Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

For instances using of_node_cmp, this has the side effect of now using
case sensitive comparisons. This should not matter for any FDT based
system which all of these are.

Cc: Chanwoo Choi <cw00.choi@samsung.com>
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: linux-pm@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>