ARM: dts: s5pv210: align USB node name with bindings

Bindings expect USB HSOTG controller node to be named "usb":

  s5pv210-torbreck.dtb: hsotg@ec000000: $nodename:0: 'hsotg@ec000000' does not match '^usb(@.*)?'

Link: https://lore.kernel.org/r/20230421095721.31857-2-krzysztof.kozlowski@linaro.org


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>