dts: arm: st: u3: Add USB

[wymcg]

Added a USB node for STM32U3 SoCs, and configured USB for the Nucleo U385RG-Q, enabling the USB samples.

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[marwaiehm-st]

Suggested change

	clocks = <&rcc STM32_CLOCK(APB2, 24)>,
	<&rcc STM32_SRC_HSI48 ICLK_SEL(0)>;
	clocks = <&rcc STM32_CLOCK(APB2, 24)>,
	<&rcc STM32_SRC_HSI48 ICLK_SEL(0)>;