SDL: docs: Updated SDL_Vulkan_GetInstanceExtensions info in README-migration.md.

From 5b3a2c6df66a58f8694ccb917f7f5641cf699b2d Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Thu, 2 Nov 2023 14:57:13 -0400
Subject: [PATCH] docs: Updated SDL_Vulkan_GetInstanceExtensions info in
 README-migration.md.

Reference PR #8457.
---
 docs/README-migration.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/README-migration.md b/docs/README-migration.md
index 85949df58155..6d0c9131f181 100644
--- a/docs/README-migration.md
+++ b/docs/README-migration.md
@@ -1293,7 +1293,7 @@ The following symbols have been renamed:
 
 ## SDL_vulkan.h
 
-SDL_Vulkan_GetInstanceExtensions() no longer takes a window parameter.
+SDL_Vulkan_GetInstanceExtensions() no longer takes a window parameter, and no longer makes the app allocate query/allocate space for the result, instead returning a static const internal string.
 
 SDL_Vulkan_GetVkGetInstanceProcAddr() now returns `SDL_FunctionPointer` instead of `void *`, and should be cast to PFN_vkGetInstanceProcAddr.