YJIT, ZJIT: enhance clippy settings and fix lint

[jesse-shopify]

Move clippy lint configuration (which is declarative) from lib.rs into Cargo.toml.

Lint Groups

Forbid: correctness, suspicious, perf
Deny: complexity
Allow: pedantic, style, restricted

Can be overridden with allow in code or with specific lint?

• Deny = Yes
• Forbid = No

Individual Lints

Allow from complexity

too_many_arguments = "allow"
identity_op = "allow"

Deny from allowed groups

ptr_arg = "forbid"
ref_option = "forbid"
inefficient_to_string = "forbid"
from_over_into = "forbid"
unwrap_or_default = "forbid"
redundant_static_lifetimes = "forbid"
match_like_matches_macro = "forbid"
field_reassign_with_default = "forbid"
inherent_to_string = "forbid"
owned_cow = "forbid"
redundant_clone = "forbid"
str_to_string = "forbid"
single_char_pattern = "forbid"
single_char_add_str = "forbid"
unnecessary_owned_empty_strings = "forbid"
manual_string_new = "forbid"

Resources

• https://doc.rust-lang.org/clippy/lints.html
• https://rust-lang.github.io/rust-clippy/master/index.html