Add diagnostic explaining STATUS_STACK_BUFFER_OVERRUN not only being

used for stack buffer overruns if link.exe exits with that exit code

`STATUS_STACK_BUFFER_OVERRUN` is also used for fast abnormal program
termination, e.g. by abort(). Emit a special diagnostic to let people
know that this most likely doesn't indicate a stack buffer overrun.

compiler/rustc_codegen_ssa/src/errors.rs

@@ -550,6 +550,11 @@ impl<G: EmissionGuarantee> Diagnostic<'_, G> for LinkingFailed<'_> {
 #[diag(codegen_ssa_link_exe_unexpected_error)]
 pub(crate) struct LinkExeUnexpectedError;
 
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_link_exe_status_stack_buffer_overrun)]
+#[note]
+pub(crate) struct LinkExeStatusStackBufferOverrun;
+
 #[derive(Diagnostic)]
 #[diag(codegen_ssa_repair_vs_build_tools)]
 pub(crate) struct RepairVSBuildTools;