[lld-macho] Don't rewrite -rpath arguments in response file

[int3]

Summary

We only want to rewrite paths to files that the linker looks up. Files
under RPATH are looked up at runtime by dyld.

lld/MachO/DriverUtils.cpp

case OPT_load_hidden:
       os << arg->getSpelling() << " "
          << quote(rewriteInputPath(arg->getValue())) << "\n";
       break;
     case OPT_F:
     case OPT_L:
     case OPT_bundle_loader:
     case OPT_exported_symbols_list:
     case OPT_order_file:
-    case OPT_rpath:
     case OPT_syslibroot:
     case OPT_unexported_symbols_list:
       os << arg->getSpelling() << " " << quote(rewritePath(arg->getValue()))
          << "\n";
       break;
     case OPT_sectcreate:
       os << arg->getSpelling() << " " << quote(arg->getValue(0)) << " "
          << quote(arg->getValue(1)) << " "

lld/test/MachO/reproduce.s

 # REQUIRES: x86, shell
 
 # RUN: rm -rf %t.dir
 # RUN: mkdir -p %t.dir/build1
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos %s -o %t.dir/build1/foo.o
 # RUN: echo '_main' > %t.dir/main.exports
 # RUN: echo '_main' > %t.dir/main.order
 # RUN: echo 'not a virus' > %t.dir/sectdata.txt
 # RUN: cd %t.dir
 # RUN: %lld -platform_version macos 10.10.0 11.0 \
 # RUN:     -exported_symbols_list main.exports \
 # RUN:     -order_file main.order \
 # RUN:     -sectcreate __COMPLETELY __legit sectdata.txt \
+# RUN:     -rpath /usr/lib/swift \
 # RUN:     build1/foo.o -o bar --reproduce repro1.tar
 
 # RUN: tar tf repro1.tar | FileCheck -DPATH='%:t.dir' --check-prefix=LIST %s
 # LIST: repro1/response.txt
 # LIST: [[PATH]]/main.exports
 # LIST: [[PATH]]/build1/foo.o
 # LIST: [[PATH]]/main.order
 # LIST: [[PATH]]/sectdata.txt
 
 # RUN: tar xf repro1.tar
 # RUN: cmp build1/foo.o repro1/%:t.dir/build1/foo.o
 # RUN: diff main.exports repro1/%:t.dir/main.exports
 # RUN: diff main.order repro1/%:t.dir/main.order
 # RUN: diff sectdata.txt repro1/%:t.dir/sectdata.txt
 # RUN: FileCheck %s --check-prefix=RSP1 < repro1/response.txt
 # RSP1:      {{^}}-platform_version macos 10.10.0 11.0{{$}}
 # RSP1-NEXT: -exported_symbols_list [[BASEDIR:.+]]/main.exports
 # RSP1-NEXT: -order_file [[BASEDIR]]/main.order
 # RSP1-NEXT: -sectcreate __COMPLETELY __legit [[BASEDIR]]/sectdata.txt
+# RSP1-NEXT: -rpath /usr/lib/swift
 # RSP1-NOT:  {{^}}repro1{{[/\\]}}
 # RSP1-NEXT: [[BASEDIR]]/build1/foo.o
 # RSP1-NEXT: -o bar
 # RSP1-NOT:  --reproduce
 
 # RUN: FileCheck %s --check-prefix=VERSION < repro1/version.txt
 # VERSION: LLD