Add -Zembed-metadata CLI option

compiler/rustc_session/src/options.rs

@@ -2175,6 +2175,8 @@ options! {
         them only if an error has not been emitted"),
     ehcont_guard: bool = (false, parse_bool, [TRACKED],
         "generate Windows EHCont Guard tables"),
+    embed_metadata: bool = (true, parse_bool, [TRACKED],
+        "embed metadata in rlibs and dylibs (default: yes)"),
     embed_source: bool = (false, parse_bool, [TRACKED],
         "embed source text in DWARF debug sections (default: no)"),
     emit_stack_sizes: bool = (false, parse_bool, [UNTRACKED],