Fix UsbDm and UsbDp for Gpio19 and Gpio20

[GrantMoyer]

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We appreciate the time and effort you've put into this pull request.
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Submission Checklist 📝

• I have updated existing examples or added new ones (if applicable).
• I have used cargo xtask fmt-packages command to ensure that all changed code is formatted correctly.
• My changes were added to the CHANGELOG.md in the proper section.
• My changes are in accordance to the esp-rs API guidelines

Extra:

• I have read the CONTRIBUTING.md guide and followed its instructions.

Pull Request Details 📖

Description

GPIO pins 19 and 20 had USB D- and D+ swapped. This change fixes which pin is which USB data line according to the pin descriptions in the ESP32-S2 and ESP32-S3 data sheets (sections 2.2 and 2.3.2 respectively). Since these GpioPins are only used by Usb for lifetime tracking, and UsbDp and UsbDm are always used as a pair, this change is only semantic and doesn't affect functionality.

Testing

I checked that the updated usb_serial and embassy_usb_serial examples build with the esp-hal changes.

[jessebraham]

Good catch, thanks!

[MabezDev]

Thanks!