Add stm327xx-hal benchmark #802

Before: ``` collector error: Failed to benchmark 'stm32f4', recorded: failed to obtain pkgid in '"/tmp/.tmpLF63db"' ``` After: ``` collector error: Failed to benchmark 'stm32f4', recorded: failed to obtain pkgid in '"/tmp/.tmpAmktlm"': expected success, got exit code: 101 stderr=error: a Cargo.lock must exist for this command stdout= ```

This confuses rustc-fake, which expects to only be run when profiled (on the code being timed, not on dependencies).