[lld/LTO] Remove unused Path parameter to AddBufferFn

[tejohnson]

Summary

With D43396, no clients use the Path parameter anymore.
This is the lld side fix with D43400.

Depends on D43396 and D43400.

COFF/LTO.cpp

std::vector<StringRef> BitcodeCompiler::compile() {
   Buff.resize(MaxTasks);
   Files.resize(MaxTasks);
 
   // The /lldltocache option specifies the path to a directory in which to cache
   // native object files for ThinLTO incremental builds. If a path was
   // specified, configure LTO to use it as the cache directory.
   lto::NativeObjectCache Cache;
   if (!Config->LTOCache.empty())
-    Cache = check(
-        lto::localCache(Config->LTOCache,
-                        [&](size_t Task, std::unique_ptr<MemoryBuffer> MB,
-                            StringRef Path) { Files[Task] = std::move(MB); }));
+    Cache = check(lto::localCache(
+        Config->LTOCache, [&](size_t Task, std::unique_ptr<MemoryBuffer> MB) {
+          Files[Task] = std::move(MB);
+        }));
 
   checkError(LTOObj->run(
       [&](size_t Task) {
         return llvm::make_unique<lto::NativeObjectStream>(
             llvm::make_unique<raw_svector_ostream>(Buff[Task]));
       },
       Cache));
 

ELF/LTO.cpp

std::vector<InputFile *> BitcodeCompiler::compile() {
 
   // The --thinlto-cache-dir option specifies the path to a directory in which
   // to cache native object files for ThinLTO incremental builds. If a path was
   // specified, configure LTO to use it as the cache directory.
   lto::NativeObjectCache Cache;
   if (!Config->ThinLTOCacheDir.empty())
     Cache = check(
         lto::localCache(Config->ThinLTOCacheDir,
-                        [&](size_t Task, std::unique_ptr<MemoryBuffer> MB,
-                            StringRef Path) { Files[Task] = std::move(MB); }));
+                        [&](size_t Task, std::unique_ptr<MemoryBuffer> MB) {
+                          Files[Task] = std::move(MB);
+                        }));
 
   checkError(LTOObj->run(
       [&](size_t Task) {
         return llvm::make_unique<lto::NativeObjectStream>(
             llvm::make_unique<raw_svector_ostream>(Buff[Task]));
       },
       Cache));