Remove in_band_lifetimes from rustc_mir_transform

This one is a heavy `'tcx` user.

Two interesting ones:

This one had the `'tcx` declared on the function, despite the trait taking a `'tcx`:
```diff
-impl Visitor<'_> for UsedLocals {
+impl<'tcx> Visitor<'tcx> for UsedLocals {
     fn visit_statement(&mut self, statement: &Statement<'tcx>, location: Location) {
```

This one use in-band for one, and underscore for the other:
```diff
-pub fn remove_dead_blocks(tcx: TyCtxt<'tcx>, body: &mut Body<'_>) {
+pub fn remove_dead_blocks<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
```

compiler/rustc_mir_transform/src/coverage/mod.rs

@@ -443,7 +443,7 @@ impl<'a, 'tcx> Instrumentor<'a, 'tcx> {
 }
 
 fn inject_edge_counter_basic_block(
-    mir_body: &mut mir::Body<'tcx>,
+    mir_body: &mut mir::Body<'_>,
     from_bb: BasicBlock,
     to_bb: BasicBlock,
 ) -> BasicBlock {
@@ -466,7 +466,7 @@ fn inject_edge_counter_basic_block(
 }
 
 fn inject_statement(
-    mir_body: &mut mir::Body<'tcx>,
+    mir_body: &mut mir::Body<'_>,
     counter_kind: CoverageKind,
     bb: BasicBlock,
     some_code_region: Option<CodeRegion>,
@@ -488,7 +488,7 @@ fn inject_statement(
 }
 
 // Non-code expressions are injected into the coverage map, without generating executable code.
-fn inject_intermediate_expression(mir_body: &mut mir::Body<'tcx>, expression: CoverageKind) {
+fn inject_intermediate_expression(mir_body: &mut mir::Body<'_>, expression: CoverageKind) {
     debug_assert!(matches!(expression, CoverageKind::Expression { .. }));
     debug!("  injecting non-code expression {:?}", expression);
     let inject_in_bb = mir::START_BLOCK;