Better `impl`s for some `c2rust-analysis-rt` types

[kkysen]

This adds better impls for some c2rust-analysis-rt types. Namely, we

• https://github.com/immunant/c2rust/commit/8230808bc590a45a492312cf8052f944d8132ba6: match rustc's derive impls for mirrored types like Fingerprint and DefPathHash
• https://github.com/immunant/c2rust/commit/2f596ae50aac109b1eeaa15eb60e2d2265b810e4: extend those same impls to other types impled based on rustc-mirrored types, like Func (based on DefPathHash)
• https://github.com/immunant/c2rust/commit/9fac146fb2a77d7e862ecb7581041ecfbf7c8722: omit EventMetadata::debug_info from the Eq and Hash impls, as it's just extra info