repl: remove workaround for function redefinition

The issue is fixed upstream in V8. Thus we do not need this workaround
in REPL.
Refs: #548

Author: targos

lib/repl.js

@@ -567,12 +567,6 @@ function REPLServer(prompt,
         // an expression.
         cmd = `(${cmd})`;
         self.wrappedCmd = true;
-      } else {
-        // Mitigate https://github.com/nodejs/node/issues/548
-        cmd = cmd.replace(
-          /^\s*function(?:\s*(\*)\s*|\s+)([^(]+)/,
-          (_, genStar, name) => `var ${name} = function ${genStar || ''}${name}`
-        );
       }
       // Append a \n so that it will be either
       // terminated, or continued onto the next expression if it's an