Update to ESP-IDF 5.1 and add C6 and H2 support

[tannewt]

• H2 is the first ESP without wifi.
• Code size grew so 2MB and 4MB C3s have _bleio disabled to make plenty of room.
• GCC was updated so some changes are to fix new compiler errors.
• adc and dac drivers were updated to new API. (C6 only supports new adc API.)
• C6 and H2 have a new RTC peripheral, LP_AON, that is used in place of the RTC on those chips.

[dhalbert]

Thanks for bringing us up to date!

Approving, but one q about INTERNAL_LIBM. Merge when you wish.

[dhalbert]

Why did you change this to use the ESP-IDF libm?

[tannewt]

There is a rom blob (can't remember which) that links against floor(). Our implementation has it for doubles but it didn't compile. So, I switched it assuming that's what espressif uses.