yuzu-qt: Load Vulkan device info at startup

Loading it when the configuration opens now incurs a noticeable delay.
We also don't need to rediscover the same data repeatedly each time the
configuration opens.

Moves vulkan device info discovery to yuzu's startup as opposed to the
configure_graphics constructor.

src/yuzu/main.h

@@ -118,6 +118,10 @@ enum class ReinitializeKeyBehavior {
     Warning,
 };
 
+namespace VkDeviceInfo {
+class Record;
+}
+
 class GMainWindow : public QMainWindow {
     Q_OBJECT
 
@@ -418,6 +422,8 @@ private:
 
     GameListPlaceholder* game_list_placeholder;
 
+    std::vector<VkDeviceInfo::Record> vk_device_records;
+
     // Status bar elements
     QLabel* message_label = nullptr;
     QLabel* shader_building_label = nullptr;