renderer_vulkan: Throw when enumerating devices fails

Report device enumeration errors with exceptions to be consistent with
other initialization related function calls. Reduces the amount of code
to maintain.

src/video_core/vulkan_common/vulkan_instance.cpp

@@ -111,7 +111,7 @@ void RemoveUnavailableLayers(const vk::InstanceDispatch& dld, std::vector<const
 }
 } // Anonymous namespace
 
-std::pair<vk::Instance, u32> CreateInstance(Common::DynamicLibrary& library,
+std::pair<vk::Instance, u32> CreateInstance(const Common::DynamicLibrary& library,
                                             vk::InstanceDispatch& dld,
                                             Core::Frontend::WindowSystemType window_type,
                                             bool enable_debug_utils, bool enable_layers) {

src/video_core/vulkan_common/vulkan_instance.h

@@ -14,7 +14,7 @@
 namespace Vulkan {
 
 [[nodiscard]] std::pair<vk::Instance, u32> CreateInstance(
-    Common::DynamicLibrary& library, vk::InstanceDispatch& dld,
+    const Common::DynamicLibrary& library, vk::InstanceDispatch& dld,
     Core::Frontend::WindowSystemType window_type = Core::Frontend::WindowSystemType::Headless,
     bool enable_debug_utils = false, bool enable_layers = false);
 

src/video_core/vulkan_common/vulkan_wrapper.cpp

@@ -465,17 +465,13 @@ Instance Instance::Create(u32 version, Span<const char*> layers, Span<const char
     return Instance(instance, dispatch);
 }
 
-std::optional<std::vector<VkPhysicalDevice>> Instance::EnumeratePhysicalDevices() const {
+std::vector<VkPhysicalDevice> Instance::EnumeratePhysicalDevices() const {
     u32 num;
-    if (dld->vkEnumeratePhysicalDevices(handle, &num, nullptr) != VK_SUCCESS) {
-        return std::nullopt;
-    }
+    Check(dld->vkEnumeratePhysicalDevices(handle, &num, nullptr));
     std::vector<VkPhysicalDevice> physical_devices(num);
-    if (dld->vkEnumeratePhysicalDevices(handle, &num, physical_devices.data()) != VK_SUCCESS) {
-        return std::nullopt;
-    }
+    Check(dld->vkEnumeratePhysicalDevices(handle, &num, physical_devices.data()));
     SortPhysicalDevices(physical_devices, *dld);
-    return std::make_optional(std::move(physical_devices));
+    return physical_devices;
 }
 
 DebugUtilsMessenger Instance::CreateDebugUtilsMessenger(

src/video_core/vulkan_common/vulkan_wrapper.h

@@ -580,7 +580,8 @@ public:
 
     /// Enumerates physical devices.
     /// @return Physical devices and an empty handle on failure.
-    std::optional<std::vector<VkPhysicalDevice>> EnumeratePhysicalDevices() const;
+    /// @throw Exception on Vulkan error.
+    std::vector<VkPhysicalDevice> EnumeratePhysicalDevices() const;
 
     /// Creates a debug callback messenger.
     /// @throw Exception on creation failure.