vk_descriptor_pool: Add missing <algorithm> include

src/video_core/renderer_vulkan/vk_descriptor_pool.cpp

@@ -2,6 +2,7 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <algorithm>
 #include <mutex>
 #include <span>
 #include <vector>