[RuntimeDyld] Make SectionEntry's Name field a std::string.

StringRef is unsafe here, since SectionEntry instances can outlive the
ObjectFile instances they are created from.

llvm-svn: 234910

llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h

@@ -52,7 +52,7 @@ class Twine;
 class SectionEntry {
 public:
   /// Name - section name.
-  StringRef Name;
+  std::string Name;
 
   /// Address - address in the linker's memory where the section resides.
   uint8_t *Address;