Rollup merge of #105234 - JakobDegen:unneeded-field, r=oli-obk

Remove unneeded field from `SwitchTargets`

This had a fixme already. The only change in behavior is that the mir dumps now no longer contains labels for the types of the integers on the edges of a switchint:

Before:
![image](https://user-images.githubusercontent.com/51179609/205467622-34401a68-dca6-43eb-915e-b9fda1988860.png)

After:
![image](https://user-images.githubusercontent.com/51179609/205467634-b5b2a259-9cb4-4843-845c-592c500f0f9c.png)

I don't think that's a problem though. The information is still available to a user that really cares by checking the type of `_2`, so it honestly feels like a bit of an improvement to me.

r? mir

Author: matthiaskrgr

compiler/rustc_borrowck/src/invalidation.rs

@@ -106,7 +106,7 @@ impl<'cx, 'tcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx> {
         self.check_activations(location);
 
         match &terminator.kind {
-            TerminatorKind::SwitchInt { discr, switch_ty: _, targets: _ } => {
+            TerminatorKind::SwitchInt { discr, targets: _ } => {
                 self.consume_operand(location, discr);
             }
             TerminatorKind::Drop { place: drop_place, target: _, unwind: _ } => {

compiler/rustc_borrowck/src/lib.rs

@@ -644,7 +644,7 @@ impl<'cx, 'tcx> rustc_mir_dataflow::ResultsVisitor<'cx, 'tcx> for MirBorrowckCtx
         self.check_activations(loc, span, flow_state);
 
         match &term.kind {
-            TerminatorKind::SwitchInt { discr, switch_ty: _, targets: _ } => {
+            TerminatorKind::SwitchInt { discr, targets: _ } => {
                 self.consume_operand(loc, (discr, span), flow_state);
             }
             TerminatorKind::Drop { place, target: _, unwind: _ } => {