v0.5.7

Bounds pend on InterruptNumber directly

• svd2rust 0.18 implements only this
• cortex-m implements this for Copy + Nr

So this should be backwards compatible, and forwards compatible with the new svd2rust.

v0.5.6

This fork-only release in the 0.5 series pulls in the stack burden prevention change that will be in upstream's 0.6 series.