[ClangLinkerWrapper] Fix intermediate file naming for multi-arch compilation (#99325)

When save-temps is enabled and the given offload-archs differ
only in target features with the same arch, the intermediate
postlink.bc and postopt.bc files were getting overwritten. This
fix, suffixes the intermediate file names with the complete
TargetID.

E.g. `helloworld.amdgcn-amd-amdhsa.gfx90a:xnack+.postlink.bc`
and `helloworld.amdgcn-amd-amdhsa.gfx90a:xnack+.postopt.bc`

Author: saiislam

clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp

@@ -14,6 +14,7 @@
 //
 //===---------------------------------------------------------------------===//
 
+#include "clang/Basic/TargetID.h"
 #include "clang/Basic/Version.h"
 #include "llvm/ADT/MapVector.h"
 #include "llvm/BinaryFormat/Magic.h"
@@ -668,7 +669,8 @@ std::unique_ptr<lto::LTO> createLTO(
     ModuleHook Hook = [](size_t, const Module &) { return true; }) {
   const llvm::Triple Triple(Args.getLastArgValue(OPT_triple_EQ));
   // We need to remove AMD's target-id from the processor if present.
-  StringRef Arch = Args.getLastArgValue(OPT_arch_EQ).split(":").first;
+  StringRef TargetID = Args.getLastArgValue(OPT_arch_EQ);
+  StringRef Arch = clang::getProcessorFromTargetID(Triple, TargetID);
   lto::Config Conf;
   lto::ThinBackend Backend;
   // TODO: Handle index-only thin-LTO
@@ -712,7 +714,7 @@ std::unique_ptr<lto::LTO> createLTO(
 
   if (SaveTemps) {
     std::string TempName = (sys::path::filename(ExecutableName) + "." +
-                            Triple.getTriple() + "." + Arch)
+                            Triple.getTriple() + "." + TargetID)
                                .str();
     Conf.PostInternalizeModuleHook = [=](size_t Task, const Module &M) {
       std::string File =