settings_common: Use a vector in category linkage

Improve storage requirements.

src/common/settings_common.cpp

@@ -12,7 +12,7 @@ BasicSetting::BasicSetting(Linkage& linkage, const std::string& name, enum Categ
     : label{name}, category{category_}, id{linkage.count}, save{save_},
       runtime_modifiable{runtime_modifiable_}, specialization{specialization_},
       other_setting{other_setting_} {
-    linkage.by_category[category].push_front(this);
+    linkage.by_category[category].push_back(this);
     linkage.count++;
 }
 

src/common/settings_common.h

@@ -66,7 +66,7 @@ class Linkage {
 public:
     explicit Linkage(u32 initial_count = 0);
     ~Linkage();
-    std::map<Category, std::forward_list<BasicSetting*>> by_category{};
+    std::map<Category, std::vector<BasicSetting*>> by_category{};
     std::vector<std::function<void()>> restore_functions{};
     u32 count;
 };