base: Make Named::name() non-reference

Some of the use cases for name() inheritance may
use local strings, which complicates the use of
rvalues.

Change-Id: I22188a238dbe73a5f174f70b88bc4b8812f9d31a
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/43588
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>

src/base/named.hh

@@ -41,7 +41,7 @@ class Named
     Named(const std::string &name_) : _name(name_) { }
     virtual ~Named() = default;
 
-    virtual const std::string &name() const { return _name; }
+    virtual std::string name() const { return _name; }
 };
 
 #endif // __BASE_NAMED_HH__