SDL: Added a migration note for SDL_Vulkan_GetInstanceExtensions()

From 9ffeae7b58e24591a29c87aecc2b6922e191f916 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Sun, 8 Jan 2023 07:59:14 -0800
Subject: [PATCH] Added a migration note for SDL_Vulkan_GetInstanceExtensions()

---
 docs/README-migration.md | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/docs/README-migration.md b/docs/README-migration.md
index a18478eecb3a..955d2f77896e 100644
--- a/docs/README-migration.md
+++ b/docs/README-migration.md
@@ -848,7 +848,7 @@ If you were using this macro for other things besides SDL ticks values, you can
 
 ## SDL_version.h
 
-SDL_GetRevisionNumber() has been removed from the API, it always returned 0 in SDL 2.0
+SDL_GetRevisionNumber() has been removed from the API, it always returned 0 in SDL 2.0.
 
 
 ## SDL_video.h
@@ -875,3 +875,8 @@ The following functions have been renamed:
 
 SDL_Window id type is named SDL_WindowID
 
+
+## SDL_vulkan.h
+
+SDL_Vulkan_GetInstanceExtensions() no longer takes a window parameter.
+