[ELF] Strip directories for -Map when emitting reproducer rsp

[abrachet]

Summary

Similarly to -o output directories will not be created so -Map being
copied verbatim will likely cause ld.lld @response.txt to fail.

[MaskRay]

LGTM.

lld/ELF/DriverUtils.cpp

std::string elf::createResponseFile(const opt::InputArgList &args) {
   for (auto *arg : args) {
     switch (arg->getOption().getID()) {
     case OPT_reproduce:
       break;
     case OPT_INPUT:
       os << quote(rewritePath(arg->getValue())) << "\n";
       break;
     case OPT_o:
-      // If -o path contains directories, "lld @response.txt" will likely
-      // fail because the archive we are creating doesn't contain empty
+    case OPT_Map:
+      // If an output path contains directories, "lld @response.txt" will
+      // likely fail because the archive we are creating doesn't contain empty
       // directories for the output path (-o doesn't create directories).
       // Strip directories to prevent the issue.
-      os << "-o " << quote(path::filename(arg->getValue())) << "\n";
+      os << arg->getSpelling() << ' ' << quote(path::filename(arg->getValue()))
+         << "\n";
       break;
     case OPT_lto_sample_profile:
       os << arg->getSpelling() << quote(rewritePath(arg->getValue())) << "\n";
       break;
     case OPT_call_graph_ordering_file:
     case OPT_dynamic_list:
     case OPT_export_dynamic_symbol_list:
     case OPT_just_symbols:

lld/test/ELF/reproduce.s

 # CHECK-NEXT: repro3/{{.*}}/ver
 # CHECK-NEXT: repro3/{{.*}}/foo bar
 # CHECK-NEXT: repro3/{{.*}}/file2
 # CHECK-NEXT: repro3/{{.*}}/file
 
 ## Check that directory path is stripped from -o <file-path>
 # RUN: mkdir -p %t.dir/build4/a/b/c
 # RUN: cd %t.dir
-# RUN: ld.lld build1/foo.o -o build4/a/b/c/bar -shared --as-needed --reproduce=repro4.tar
+# RUN: ld.lld build1/foo.o -o build4/a/b/c/bar -Map build4/a/b/c/map -shared --as-needed --reproduce=repro4.tar
 # RUN: tar xOf repro4.tar repro4/response.txt | FileCheck %s --check-prefix=RSP4
 # RSP4: -o bar
+# RSP4: -Map map
 
 .globl _start
 _start:
   mov $60, %rax
   mov $42, %rdi
   syscall