Two fixes to Adafruit Circuit Playground Express

[ladyada]

hiya, we have a fixed up Variant.cpp & Variant.h that matches the current shipping hardware.
we also have a fix for "CRYSTALLESS" which will make it reliable on start (thanks @tannnewt!)

please let Phil and I know the best way to submit the two sets of changes: one is to the CPX variant files and one is to startup.c. Can do a pull request or attach a patchfile.

We'll post up on the dev list too.

[cmaglie]

Just send a PR, so we can examine it. Once merged it will be published on the next samd core release.

[ladyada]

hiya is there an ETA for the next samd core release?

[cmaglie]

Fixed by #240