vulkan: Move vk_synchronization2 to vk_synchronization

I'm about to add more stuff that isn't really for sync2 so it makes
sense to give it a slightly more generic name.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Konstantin Seurer <konstantin.seurer@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26407>

src/vulkan/runtime/meson.build

@@ -108,7 +108,7 @@ vulkan_runtime_files = files(
   'vk_sync_dummy.h',
   'vk_sync_timeline.c',
   'vk_sync_timeline.h',
-  'vk_synchronization2.c',
+  'vk_synchronization.c',
   'vk_texcompress_etc2.c',
   'vk_texcompress_etc2.h',
   'vk_video.c',