MachineFunction: Return reference from getFunction(); NFC

The Function can never be nullptr so we can return a reference.

llvm-svn: 320884
diff --git a/llvm/lib/CodeGen/ExecutionDepsFix.cpp b/llvm/lib/CodeGen/ExecutionDepsFix.cpp
index df51ecc..61ec3f4 100644
--- a/llvm/lib/CodeGen/ExecutionDepsFix.cpp
+++ b/llvm/lib/CodeGen/ExecutionDepsFix.cpp
@@ -617,7 +617,7 @@
 }
 
 bool ExecutionDepsFix::runOnMachineFunction(MachineFunction &mf) {
-  if (skipFunction(*mf.getFunction()))
+  if (skipFunction(mf.getFunction()))
     return false;
   MF = &mf;
   TII = MF->getSubtarget().getInstrInfo();