Update reproducible hashes

Support parsing old credentials

Add GitHub workflow to check that binaries are reproducible.

This permits to decode a credential of a different version without failing.

Removing support for writable flash regions permits to save 1 page in the binary
due to alignment constraints. It also permits to reduce the diff with libtock-rs
which doesn't support writable flash regions.

This commit also updates the `SyscallStorage` documentation.

Rename linker script according to the chip

The layout applies to all boards sharing the nrf52840 chip.

add 2.1 features to GetInfo

Add missing parameter that got introduced in tockloader 1.4

Adjust yapf formatter

They don't play well with DFU.