dt-bindings: power: reset: xilinx: Rename node names in examples

Rename zynqmp-power node name to power-management which is more aligned
with generic node name recommendation.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/920c839ae2c9c5803c6c08b8705a0d8338bb94bc.1703161663.git.michal.simek@amd.com


Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>