Rollup merge of #135700 - estebank:priv-field-dfv, r=wesleywiser

Emit single privacy error for struct literal with multiple private fields and add test for `default_field_values` privacy

Add test ensuring that struct with default field values is not constructable if the fields are not accessible.

Collect all unreachable fields in a single struct literal struct and emit a single error, instead of one error per private field.

```
error[E0451]: fields `beta` and `gamma` of struct `Alpha` are private
  --> $DIR/visibility.rs:18:13
   |
LL |     let _x = Alpha {
   |              ----- in this type
LL |         beta: 0,
   |         ^^^^^^^ private field
LL |         ..
   |         ^^ field `gamma` is private
```

0 files changed, 0 insertions, 0 deletions