Fix viewCFG on Linux.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96834 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/GraphWriter.cpp b/lib/Support/GraphWriter.cpp
index c8bca6e..ec84f9b 100644
--- a/lib/Support/GraphWriter.cpp
+++ b/lib/Support/GraphWriter.cpp
@@ -137,7 +137,7 @@
     args.clear();
     args.push_back(gv.c_str());
     args.push_back(PSFilename.c_str());
-    args.push_back("-spartan");
+    args.push_back("--spartan");
     args.push_back(0);
     
     ErrMsg.clear();