Implement sf::Vulkan functions

https://github.com/SFML/SFML/pull/1557

src/SFML/Window/CMakeLists.txt

@@ -29,6 +29,8 @@ set(SRC
     ${INCROOT}/Types.h
     ${SRCROOT}/VideoMode.cpp
     ${INCROOT}/VideoMode.h
+    ${SRCROOT}/Vulkan.cpp
+    ${INCROOT}/Vulkan.h
     ${SRCROOT}/Window.cpp
     ${SRCROOT}/WindowStruct.h
     ${INCROOT}/Window.h

src/SFML/Window/Vulkan.cpp

@@ -0,0 +1,54 @@
+////////////////////////////////////////////////////////////
+//
+// SFML - Simple and Fast Multimedia Library
+// Copyright (C) 2007-2023 Laurent Gomila (laurent@sfml-dev.org)
+//
+// This software is provided 'as-is', without any express or implied warranty.
+// In no event will the authors be held liable for any damages arising from the use of this software.
+//
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it freely,
+// subject to the following restrictions:
+//
+// 1. The origin of this software must not be misrepresented;
+//    you must not claim that you wrote the original software.
+//    If you use this software in a product, an acknowledgment
+//    in the product documentation would be appreciated but is not required.
+//
+// 2. Altered source versions must be plainly marked as such,
+//    and must not be misrepresented as being the original software.
+//
+// 3. This notice may not be removed or altered from any source distribution.
+//
+////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////
+// Headers
+////////////////////////////////////////////////////////////
+#include <SFML/Window/Export.h>
+#include <SFML/Window/Vulkan.h>
+#include <SFML/Window/Vulkan.hpp>
+
+#include <stdlib.h>
+#include <string.h>
+
+
+////////////////////////////////////////////////////////////
+sfBool sfVulkan_isAvailable(sfBool requireGraphics)
+{
+    return sf::Vulkan::isAvailable(requireGraphics);
+}
+
+
+////////////////////////////////////////////////////////////
+sfVulkanFunctionPointer sfVulkan_getFunction(const char* name)
+{
+    return sf::Vulkan::getFunction(name);
+}
+
+
+////////////////////////////////////////////////////////////
+const char* const* sfVulkan_getGraphicsRequiredInstanceExtensions()
+{
+    return &sf::Vulkan::getGraphicsRequiredInstanceExtensions()[0];
+}