Auto merge of #118138 - Nilstrieb:one-previous-error, r=WaffleLapkin

Fixes error count display is different when there's only one error left

Supersedes #114759

### What did I do?

I did the small change in `rustc_errors` by hand. Then I did the other changes in `/compiler` by hand, those were just find replace on `*.rs` in the workspace. The changes in run-make are find replace for `run-make` in the workspace.

All other changes are blessed using `x test TEST --bless`. I blessed the tests that were blessed in #114759.

### how to review this nightmare

ping bors with an `r+`. You should check that my logic is sound and maybe quickly scroll through the diff, but fully verifying it seems fairly hard to impossible. I did my best to do this correctly.

Thank you `@adrianEffe` for bringing this up and your initial implementation.

cc `@flip1995,` you said you want to do a subtree sync asap
cc `@RalfJung` maybe you want to do a quick subtree sync afterwards as well for Miri

r? `@WaffleLapkin`

Author: bors

tests/extern-so/fail/function_not_in_so.stderr

@@ -10,5 +10,5 @@ LL |         foo();
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/libc_pthread_create_main_terminate.stderr

@@ -2,5 +2,5 @@ error: the main thread terminated without waiting for all remaining threads
 
 note: pass `-Zmiri-ignore-leaks` to disable this check
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/libc_pthread_create_too_few_args.stderr

@@ -10,5 +10,5 @@ LL |     panic!()
    = note: inside `thread_start` at RUSTLIB/core/src/panic.rs:LL:CC
    = note: this error originates in the macro `$crate::panic::panic_2021` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/libc_pthread_create_too_many_args.stderr

@@ -10,5 +10,5 @@ LL |     panic!()
    = note: inside `thread_start` at RUSTLIB/core/src/panic.rs:LL:CC
    = note: this error originates in the macro `$crate::panic::panic_2021` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/libc_pthread_join_detached.stderr

@@ -11,5 +11,5 @@ LL |         assert_eq!(libc::pthread_join(native, ptr::null_mut()), 0);
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/libc_pthread_join_joined.stderr

@@ -11,5 +11,5 @@ LL |         assert_eq!(libc::pthread_join(native, ptr::null_mut()), 0);
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/libc_pthread_join_main.stderr

@@ -11,5 +11,5 @@ LL |             assert_eq!(libc::pthread_join(thread_id, ptr::null_mut()), 0);
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/libc_pthread_join_multiple.stderr

@@ -11,5 +11,5 @@ LL | ...   assert_eq!(libc::pthread_join(native_copy, ptr::null_mut()), 0);
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/libc_pthread_join_self.stderr

@@ -11,5 +11,5 @@ LL |             assert_eq!(libc::pthread_join(native, ptr::null_mut()), 0);
 
 note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
 
-error: aborting due to previous error
+error: aborting due to 1 previous error
 

tests/fail-dep/concurrency/unwind_top_of_stack.stderr

@@ -17,5 +17,5 @@ LL | | }
    = note: BACKTRACE:
    = note: inside `thread_start` at $DIR/unwind_top_of_stack.rs:LL:CC
 
-error: aborting due to previous error
+error: aborting due to 1 previous error