In 7b59c9e76d
linker scripts have been moved in the ld/ sub-folder for every target.
The change detection path in build.rs of every target hasn't been updated, resulting in
the build script running at every code change, rather than only when there's a change in memory.x
* make esp32c3 examples run from flash / flashable
* use gpio3 for blinky
* direct boot in Cargo.toml
* have a shared gpio impl
* use PACs from their original locations again
