Use StringRef in ARMConstantPool APIs (NFC)

llvm-svn: 283293
diff --git a/llvm/lib/Target/ARM/ARMAsmPrinter.cpp b/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
index b1b4f86..5788ce6 100644
--- a/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
+++ b/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
@@ -1054,7 +1054,7 @@
     MCSym = MBB->getSymbol();
   } else {
     assert(ACPV->isExtSymbol() && "unrecognized constant pool value");
-    const char *Sym = cast<ARMConstantPoolSymbol>(ACPV)->getSymbol();
+    auto Sym = cast<ARMConstantPoolSymbol>(ACPV)->getSymbol();
     MCSym = GetExternalSymbolSymbol(Sym);
   }