[Verifier] Add braces to satisfy buildbots. NFC

Fix build break introduced by r256691.

llvm-svn: 256692
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 20ae829..e469382 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -3082,9 +3082,10 @@
   Assert(CatchSwitch.getNumHandlers() != 0,
          "CatchSwitchInst cannot have empty handler list", &CatchSwitch);
 
-  for (BasicBlock *Handler : CatchSwitch.handlers())
+  for (BasicBlock *Handler : CatchSwitch.handlers()) {
     Assert(isa<CatchPadInst>(Handler->getFirstNonPHI()),
            "CatchSwitchInst handlers must be catchpads", &CatchSwitch, Handler);
+  }
 
   visitTerminatorInst(CatchSwitch);
 }