MachineFunction: Return reference for getFrameInfo(); NFC

getFrameInfo() never returns nullptr so we should use a reference
instead of a pointer.

llvm-svn: 277017
diff --git a/llvm/lib/Target/NVPTX/NVPTXFrameLowering.cpp b/llvm/lib/Target/NVPTX/NVPTXFrameLowering.cpp
index bbcb497..6ced2f6 100644
--- a/llvm/lib/Target/NVPTX/NVPTXFrameLowering.cpp
+++ b/llvm/lib/Target/NVPTX/NVPTXFrameLowering.cpp
@@ -32,7 +32,7 @@
 
 void NVPTXFrameLowering::emitPrologue(MachineFunction &MF,
                                       MachineBasicBlock &MBB) const {
-  if (MF.getFrameInfo()->hasStackObjects()) {
+  if (MF.getFrameInfo().hasStackObjects()) {
     assert(&MF.front() == &MBB && "Shrink-wrapping not yet supported");
     MachineInstr *MI = &MBB.front();
     MachineRegisterInfo &MR = MF.getRegInfo();