Address post-commit comments for https://reviews.llvm.org/D29596. NFCI.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294985 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit 47946ad)

Author: taewookoh

lib/CodeGen/MachineBasicBlock.cpp

@@ -1149,7 +1149,7 @@ MachineBasicBlock::findDebugLoc(instr_iterator MBBI) {
 /// Return UnknownLoc if there is none.
 DebugLoc
 MachineBasicBlock::findBranchDebugLoc() {
-  DebugLoc DL {};
+  DebugLoc DL;
   auto TI = getFirstTerminator();
   while (TI != end() && !TI->isBranch())
     ++TI;