Add support for STM32H523/STM32H533

[astapleton]

This is a tracking issue for the changes required to add support for the STM32H523/STM32H533 group of processors to the existing functionality.

• Integrate stm32h5 PAC with STM32H523/STM32H533 support (need new stm32h5-staging release, also see Add H523 and H533 stm32-rs#1122)
• Define GPIOs in GPIO driver
• Define I2C pins in I2C driver (WIP - see i2c: Add I2C Controller implementation #27)
• Define SPI pins in SPI driver (WIP)

Also see #38

[usbalbin]

Aside from any potential bugs, H523 and H533 support has now been merged in the pac

[astapleton]

Aside from any potential bugs, H523 and H533 support has now been merged in the pac

We also need the stm32h5-staging crate to be updated to bring in those changes (instead of pointing the HAL at the nightlies and accidentally bringing in new breaking changes). @burrbull is this something you could do now or should we wait for a wider stm32-rs update?