Fix -Wsizeof-array-argument compiler warning.

src/node.cc

@@ -2790,7 +2790,7 @@ char** Init(int argc, char *argv[]) {
     // a breakpoint on the first line of the startup script
     v8argc += 2;
     v8argv = new char*[v8argc];
-    memcpy(v8argv, argv, sizeof(argv) * option_end_index);
+    memcpy(v8argv, argv, sizeof(*argv) * option_end_index);
     v8argv[option_end_index] = const_cast<char*>("--expose_debug_as");
     v8argv[option_end_index + 1] = const_cast<char*>("v8debug");
   }