[NFC][MIRPrinter] Use `std::move` to avoid copy (#157832)

diff --git a/llvm/lib/CodeGen/MIRPrinter.cpp b/llvm/lib/CodeGen/MIRPrinter.cpp
index 7cc9192..91a21a4 100644
--- a/llvm/lib/CodeGen/MIRPrinter.cpp
+++ b/llvm/lib/CodeGen/MIRPrinter.cpp
@@ -627,7 +627,7 @@
     StrOS << printMBBReference(*MBB);
     Entry.Point = StrOS.str().str();
     Str.clear();
-    YamlSRPoints.push_back(Entry);
+    YamlSRPoints.push_back(std::move(Entry));
   }
 }