frontend/dri: don't call set_damage_region with a null resource

This can happen if texture allocation failed.

Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34668>

src/gallium/frontends/dri/dri_drawable.c

@@ -96,9 +96,11 @@ dri_st_framebuffer_validate(struct st_context *st,
        pscreen->set_damage_region) {
       struct pipe_resource *resource = textures[ST_ATTACHMENT_BACK_LEFT];
 
-      pscreen->set_damage_region(pscreen, resource,
-                                 drawable->num_damage_rects,
-                                 drawable->damage_rects);
+      if (resource) {
+         pscreen->set_damage_region(pscreen, resource,
+                                    drawable->num_damage_rects,
+                                    drawable->damage_rects);
+      }
    }
 
    if (!out)

src/intel/ci/iris-kbl-fails.txt

@@ -10,8 +10,8 @@ glx@glx-swap-pixmap-bad,Fail
 #   Value in failed request:  0x1e
 #   Serial number of failed request:  1177
 #   Current serial number in output stream:  1181
-glx@glx-visuals-depth -pixmap,Crash
-glx@glx-visuals-stencil -pixmap,Crash
+glx@glx-visuals-depth -pixmap,Fail
+glx@glx-visuals-stencil -pixmap,Fail
 
 spec@!opengl 1.0@rasterpos,Fail