ModuleObjCTrace/CAS: compute objc trace file paths via the canoical supplementary output paths computation

CAS support in compiler relies on supplementary paths to decide the mapping between input and output files. Therefore, we
have to compute the paths of the module ObjC trace files in this canonical place to have CAS support for
this newly added ObjC message trace files.

include/swift/Basic/FileTypes.def

@@ -73,6 +73,7 @@ TYPE("tbd",                 TBD,                       "tbd",             "")
 // engineers can see more details on the "Swift module traces" page in the
 // Swift section of the internal wiki.
 TYPE("module-trace",        ModuleTrace,               "trace.json",      "")
+TYPE("module-objc-trace",   ModuleObjCTrace,           "",                "")
 
 // Complete dependency information for the given Swift files as JSON.
 TYPE("json-dependencies",   JSONDependencies,          "dependencies.json",      "")

include/swift/Basic/SupplementaryOutputPaths.def

@@ -106,6 +106,7 @@ OUTPUT(FixItsOutputPath, TY_SwiftFixIt)
 /// to each .swiftmodule that was loaded while building module NAME for target
 /// TARGET. This format is subject to arbitrary change, however.
 OUTPUT(LoadedModuleTracePath, TY_ModuleTrace)
+OUTPUT(ModuleObjCTracePath,   TY_ModuleObjCTrace)
 
 /// The path to which we should output a TBD file.
 ///