[StatepointLowering] remove unused parameter. NFC

[craig.topper]

LGTM

llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp

static void reservePreviousStackSlotForValue(const Value *IncomingValue,
   Builder.StatepointLowering.setLocation(Incoming, Loc);
 }
 
 /// Extract call from statepoint, lower it and return pointer to the
 /// call node. Also update NodeMap so that getValue(statepoint) will
 /// reference lowered call result
 static std::pair<SDValue, SDNode *> lowerCallFromStatepointLoweringInfo(
     SelectionDAGBuilder::StatepointLoweringInfo &SI,
-    SelectionDAGBuilder &Builder, SmallVectorImpl<SDValue> &PendingExports) {
+    SelectionDAGBuilder &Builder) {
   SDValue ReturnValue, CallEndVal;
   std::tie(ReturnValue, CallEndVal) =
       Builder.lowerInvokable(SI.CLI, SI.EHPadBB);
   SDNode *CallEnd = CallEndVal.getNode();
 
   // Get a call instruction from the call sequence chain.  Tail calls are not
   // allowed.  The following code is essentially reverse engineering X86's
   // LowerCallTo.
#endif
 
   // Now that we've emitted the spills, we need to update the root so that the
   // call sequence is ordered correctly.
   SI.CLI.setChain(getRoot());
 
   // Get call node, we will replace it later with statepoint
   SDValue ReturnVal;
   SDNode *CallNode;
-  std::tie(ReturnVal, CallNode) =
-      lowerCallFromStatepointLoweringInfo(SI, *this, PendingExports);
+  std::tie(ReturnVal, CallNode) = lowerCallFromStatepointLoweringInfo(SI, *this);
 
   // Construct the actual GC_TRANSITION_START, STATEPOINT, and GC_TRANSITION_END
   // nodes with all the appropriate arguments and return values.
 
   // Call Node: Chain, Target, {Args}, RegMask, [Glue]
   SDValue Chain = CallNode->getOperand(0);
 
   SDValue Glue;