dt-bindings: phy: qcom,qmp: fix child node description

Fix the incorrect description of the child nodes which claimed that one
node is required per lane rather than per PHY.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20220830112923.3725-5-johan+linaro@kernel.org


Signed-off-by: Vinod Koul <vkoul@kernel.org>