SDL: wayland: Check the relative pointer handle before destroying (19c3e)

SDL Commits
1 
From 19c3e125ba71e4667743316f606872cc39f25a81 Mon Sep 17 00:00:00 2001
From: Frank Praznik <[EMAIL REDACTED]>
Date: Sun, 29 Oct 2023 14:12:38 -0400
Subject: [PATCH] wayland: Check the relative pointer handle before destroying

If the relative protocol is unsupported, this will always be null and the destroy function won't be called.

(cherry picked from commit 0e87b71d08c75af8c4b02808038825d3b16bf854)
---
 src/video/wayland/SDL_waylandevents.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/video/wayland/SDL_waylandevents.c b/src/video/wayland/SDL_waylandevents.c
index 39956c817cf0..2b87925321a8 100644
--- a/src/video/wayland/SDL_waylandevents.c
+++ b/src/video/wayland/SDL_waylandevents.c
@@ -2668,8 +2668,10 @@ int Wayland_input_unlock_pointer(struct SDL_WaylandInput *input)
         w->locked_pointer = NULL;
     }
 
-    zwp_relative_pointer_v1_destroy(input->relative_pointer);
-    input->relative_pointer = NULL;
+    if (input->relative_pointer) {
+        zwp_relative_pointer_v1_destroy(input->relative_pointer);
+        input->relative_pointer = NULL;
+    }
 
     d->relative_mouse_mode = 0;