[PPC] Silence warning in Release builds.

llvm-svn: 294791
diff --git a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
index 657423f..2cef2d0 100644
--- a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -1105,8 +1105,7 @@
     // of instructions change.
     const MachineInstr *Next = [&] {
       MachineBasicBlock::const_iterator It(MI);
-      const MachineBasicBlock *MBB = MI->getParent();
-      assert(It != MBB->end());
+      assert(It != MI->getParent()->end());
       ++It;
       assert(It->isReturn());
       return &*It;