Codechange: Initialise/reset font cache with FontSizes bitset. (#14448)

Instead of choosing either "Normal/Small/Large" or "Monospace", use an EnumBitSet to allow any combination.

src/openttd.cpp

@@ -700,7 +700,7 @@ int openttd_main(std::span<std::string_view> arguments)
 	InitializeLanguagePacks();
 
 	/* Initialize the font cache */
-	InitFontCache(false);
+	InitFontCache(FONTSIZES_REQUIRED);
 
 	/* This must be done early, since functions use the SetWindowDirty* calls */
 	InitWindowSystem();