SAMD21 TCC1 can seemingly not be used on pin PA24

[spiderkeys]

With the RIOT firmware, the chip is hard faulting when we call pwm_set() on TCC1, channel 2. All of the pwm_config_t descriptors look fine, and there are no invalid array accesses. Ran traces on all other functionality and pwm_init is successful for TCC1.

My guess is that it may not be possible to use PA24 and PA25 without some kind of special configuration as those pins also support USB and have some special notes in the datasheet. They can still be muxed as a GPIO output, seemingly. This could also be a driver issue for this specific TCC instance in RIOT, but based on my review of the code, I didn't find anything wrong and all of the pointers had correct addresses when referencing it.

This only impacts Rev9 minimally (have to fall back to using CGPIOLight instead of CPWMLight), but is something to be aware of if we try to use those pins or TCC1 in the future.