Add `DebugOptions::show_unaligned` #12848

Job	Run time
Check wasm32 + wasm-bindgen	2m 21s
Format + check + test	16m 15s
android	26s
cargo-deny aarch64-apple-darwin	37s
Check wasm32+atomics	1m 25s
ios	21s
cargo-deny aarch64-linux-android	39s
Check Windows	1m 53s
cargo-deny i686-pc-windows-gnu	37s
cargo-deny i686-pc-windows-msvc	39s
cargo-deny i686-unknown-linux-gnu	40s
cargo-deny wasm32-unknown-unknown	42s
cargo-deny x86_64-apple-darwin	38s
cargo-deny x86_64-pc-windows-gnu	37s
cargo-deny x86_64-pc-windows-msvc	39s
cargo-deny x86_64-unknown-linux-gnu	39s
cargo-deny x86_64-unknown-linux-musl	40s
cargo-deny x86_64-unknown-redox	38s
	30m 26s

Provide feedback