buffer_cache: Use boost::intrusive::set for caching

Instead of using boost::icl::interval_map for caching, use
boost::intrusive::set. interval_map is intended as a container where the
keys can overlap with one another; we don't need this for caching
buffers and a std::set-like data structure that allows us to search with
lower_bound is enough.

src/video_core/renderer_vulkan/vk_buffer_cache.cpp

@@ -7,6 +7,7 @@
 #include <memory>
 
 #include "core/core.h"
+#include "video_core/buffer_cache/buffer_cache.h"
 #include "video_core/renderer_vulkan/vk_buffer_cache.h"
 #include "video_core/renderer_vulkan/vk_device.h"
 #include "video_core/renderer_vulkan/vk_scheduler.h"

src/video_core/renderer_vulkan/vk_fence_manager.h

@@ -7,6 +7,7 @@
 #include <memory>
 
 #include "video_core/fence_manager.h"
+#include "video_core/renderer_vulkan/vk_buffer_cache.h"
 #include "video_core/renderer_vulkan/wrapper.h"
 
 namespace Core {