Driver: Add -mlinker-version=, which forwards to -target-linker-version.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@110872 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 8ca3c43..cc00804 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -1003,6 +1003,12 @@
     break;
   }
 
+  // Pass the linker version in use.
+  if (Arg *A = Args.getLastArg(options::OPT_mlinker_version_EQ)) {
+    CmdArgs.push_back("-target-linker-version");
+    CmdArgs.push_back(A->getValue(Args));
+  }
+
   // -mno-omit-leaf-frame-pointer is default.
   if (Args.hasFlag(options::OPT_momit_leaf_frame_pointer,
                    options::OPT_mno_omit_leaf_frame_pointer, false))