simplify `ast_fragments!`

The syntax and meaning of this macro are not very intuitive as its just a large dump of function names and has some special cases.
Each commit should be a small improvement that can be evaluated on its own.

…uwer

Rollup of 13 pull requests

Successful merges:

 - #155249 (Fix: On wasm targets, call `panic_in_cleanup` if panic occurs in cleanup)
 - #155853 (Use `_mcount` as the mcount symbol name on RISC-V Linux GNU targets)
 - #155919 (simplify `ast_fragments!`)
 - #155939 (Add feature gate for view_types experiment)
 - #155974 (add `c_variadic_experimental_arch` feature)
 - #155991 (Catch unwinds from the global ctxt callback to complete queries profiling data in more cases)
 - #156003 (Pass Session to optimize_and_codegen_fat_lto)
 - #153566 (Add suggestion for E0401 on inner const items)
 - #154610 (Suggest public re-exports when a private module makes an import path inaccessible)
 - #155523 (Reorganize `tests/ui/issues/` - 02)
 - #155980 (Move `feature*` methods from `parse` mod to `errors` mod.)
 - #155987 (Make lifting infallible)
 - #155988 (tests/run-make/print-cfg: add Android target_env case)

Rollup of 19 pull requests

Successful merges:

 - #155237 (Disentangle AST crates and error crates)
 - #155249 (Fix: On wasm targets, call `panic_in_cleanup` if panic occurs in cleanup)
 - #155853 (Use `_mcount` as the mcount symbol name on RISC-V Linux GNU targets)
 - #155919 (simplify `ast_fragments!`)
 - #155939 (Add feature gate for view_types experiment)
 - #155954 (rustdoc: preserve parent doc cfg for `macro_export` macros)
 - #155974 (add `c_variadic_experimental_arch` feature)
 - #155991 (Catch unwinds from the global ctxt callback to complete queries profiling data in more cases)
 - #156003 (Pass Session to optimize_and_codegen_fat_lto)
 - #153566 (Add suggestion for E0401 on inner const items)
 - #154610 (Suggest public re-exports when a private module makes an import path inaccessible)
 - #155523 (Reorganize `tests/ui/issues/` - 02)
 - #155821 (c-variadic: document `Clone` and `Drop` instances and require `VaArgSafe: Copy`)
 - #155980 (Move `feature*` methods from `parse` mod to `errors` mod.)
 - #155987 (Make lifting infallible)
 - #155988 (tests/run-make/print-cfg: add Android target_env case)
 - #156000 (Fix ICE when using -Zinstrument-mcount and -Clinker-flavor=lld)
 - #156002 (Allow to use `Diagnostic` directly in `SharedContext::emit_lint`)
 - #156015 (rustc-dev-guide subtree update)