Local fuzzing fails

[kaczmarczyck]

The latest version of cargo fuzz does not work with our toolchain. As a workaround, install an older version

cargo +stable install cargo-fuzz --version ^0.10

or fuzz with a slightly newer toolchain:

cargo +nightly-2021-12-25 fuzz run fuzz_target_process_ctap2_make_credential

This will be fixed after a bigger refactoring to make the CTAP code independent from specific hardware and Tock.