[llvm] Ensure newlines at the end of files (NFC)

This patch eliminates pesky "No newline at end of file" messages from
git diff.
diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 61b2611..bd0f2ec 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -6246,4 +6246,4 @@
   MIRBuilder.buildOr(DstReg, NewOp1, NewOp2);
   MI.eraseFromParent();
   return Legalized;
-}
\ No newline at end of file
+}