Disable "split dwarf inlining" by default.

This matches clang's behavior and makes split-debuginfo behave as expected (i.e. actually split the debug info).

Fixes #106592

Author: khuey

compiler/rustc_session/src/options.rs

@@ -1570,7 +1570,7 @@ options! {
     /// o/w tests have closure@path
     span_free_formats: bool = (false, parse_bool, [UNTRACKED],
         "exclude spans when debug-printing compiler state (default: no)"),
-    split_dwarf_inlining: bool = (true, parse_bool, [TRACKED],
+    split_dwarf_inlining: bool = (false, parse_bool, [TRACKED],
         "provide minimal debug info in the object/executable to facilitate online \
          symbolication/stack traces in the absence of .dwo/.dwp files when using Split DWARF"),
     split_dwarf_kind: SplitDwarfKind = (SplitDwarfKind::Split, parse_split_dwarf_kind, [TRACKED],