lv-tool: Resolve strcmp duplication around actors to always exclude from cycling

(based on 0.4.x commit 6ce0880)

Author: hartwork

libvisual/tools/lv-tool/lv-tool.cpp

@@ -32,6 +32,7 @@
 #include <atomic>
 #include <stdexcept>
 #include <iostream>
+#include <unordered_set>
 #include <string>
 #include <cstdio>
 #include <cstdlib>
@@ -56,6 +57,11 @@
 
 namespace {
 
+  const std::unordered_set<std::string> actors_to_skip {
+      "gdkpixbuf",
+      "gstreamer"
+  };
+
   std::string actor_name;
   std::string input_name = DEFAULT_INPUT;
   std::string morph_name = DEFAULT_MORPH;
@@ -390,8 +396,7 @@ namespace {
 
       // Always skip actors that are of little interest to end users,
       // while allowing explicit "--actor (gdkpixbuf|gstreamer)".
-      if (strcmp (new_name, "gdkpixbuf") == 0 \
-            || strcmp (new_name, "gstreamer") == 0) {
+      if (actors_to_skip.contains (new_name)) {
           return cycle_actor_name (new_name, dir);
       }