Use gv's --spartan option, which trades away an extra row of UI buttons
for more space for displaying the graph.

llvm-svn: 49730
diff --git a/llvm/lib/Support/GraphWriter.cpp b/llvm/lib/Support/GraphWriter.cpp
index b41e597..aad1818 100644
--- a/llvm/lib/Support/GraphWriter.cpp
+++ b/llvm/lib/Support/GraphWriter.cpp
@@ -57,6 +57,7 @@
     sys::Path gv(LLVM_PATH_GV);
     args.clear();
     args.push_back(gv.c_str());
+    args.push_back("--spartan");
     args.push_back(PSFilename.c_str());
     args.push_back(0);