Auto merge of #119968 - clubby789:unused-feature, r=compiler-errors

Remove unused/unnecessary features

~~The bulk of the actual code changes here is replacing try blocks with equivalent closures. I'm not entirely sure that's a good idea since it may have perf impact, happy to revert if that's the case/the change is unwanted.~~

I also removed a lot of `recursion_limit = "256"` since everything seems to build fine without that and most don't have any comment justifying it.

compiler/rustc_mir_transform/src/lib.rs

@@ -14,11 +14,9 @@
 #![feature(never_type)]
 #![feature(option_get_or_insert_default)]
 #![feature(round_char_boundary)]
-#![feature(trusted_step)]
 #![feature(try_blocks)]
 #![feature(yeet_expr)]
 #![feature(if_let_guard)]
-#![recursion_limit = "256"]
 
 #[macro_use]
 extern crate tracing;