fixup! XFAIL on Linux

Author: Michael137

lldb/test/API/lang/cpp/decl-from-submodule/TestDeclFromSubmodule.py

@@ -11,6 +11,8 @@
 class DeclFromSubmoduleTestCase(TestBase):
     # Requires DWARF debug info which is not retained when linking with link.exe.
     @skipIfWindows
+    # Lookup for decls in submodules fails in Linux
+    @expectedFailureAll(oslist=["linux"])
     def test_expr(self):
         self.build()
         lldbutil.run_to_source_breakpoint(self, "return 0", lldb.SBFileSpec("main.cpp"))