Revert "Produce .dwo file for Packed as well"

This reverts commit 3281022.

Author: cbeuw

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -904,14 +904,17 @@ pub(crate) unsafe fn codegen(
                     .generic_activity_with_arg("LLVM_module_codegen_emit_obj", &module.name[..]);
 
                 let dwo_out = cgcx.output_filenames.temp_path_dwo(module_name);
-                let dwo_out = if cgcx.target_can_use_split_dwarf
-                    && cgcx.split_debuginfo != SplitDebuginfo::Off
-                {
-                    // Emit (a subset of the) DWARF into a separate file in split mode.
-                    Some(dwo_out.as_path())
-                } else {
+                let dwo_out = match cgcx.split_debuginfo {
                     // Don't change how DWARF is emitted in single mode (or when disabled).
-                    None
+                    SplitDebuginfo::Off | SplitDebuginfo::Packed => None,
+                    // Emit (a subset of the) DWARF into a separate file in split mode.
+                    SplitDebuginfo::Unpacked => {
+                        if cgcx.target_can_use_split_dwarf {
+                            Some(dwo_out.as_path())
+                        } else {
+                            None
+                        }
+                    }
                 };
 
                 with_codegen(tm, llmod, config.no_builtins, |cpm| {
@@ -948,7 +951,7 @@ pub(crate) unsafe fn codegen(
 
     Ok(module.into_compiled_module(
         config.emit_obj != EmitObj::None,
-        cgcx.target_can_use_split_dwarf && cgcx.split_debuginfo != SplitDebuginfo::Off,
+        cgcx.target_can_use_split_dwarf && cgcx.split_debuginfo == SplitDebuginfo::Unpacked,
         config.emit_bc,
         &cgcx.output_filenames,
     ))