zink: handle NULL views in zink_set_sampler_views

Passing NULL for the views parameter should be the same as passing an
array of NULL, according to the documentation. So let's respect that
detail.

This fixes a crash when using GALLIUM_HUD.

Fixes: 8d46e35d16e ("zink: introduce opengl over vulkan")
Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8564>
(cherry picked from commit 333730405de28153f2378d498e45cb82024fc230)
diff --git a/.pick_status.json b/.pick_status.json
index dab0ef8..6afddcf 100644
--- a/.pick_status.json
+++ b/.pick_status.json
@@ -418,7 +418,7 @@
         "description": "zink: handle NULL views in zink_set_sampler_views",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "master_sha": null,
         "because_sha": "8d46e35d16e3936968958bcab86d61967a673305"
     },
diff --git a/src/gallium/drivers/zink/zink_context.c b/src/gallium/drivers/zink/zink_context.c
index 67465b8..b888274 100644
--- a/src/gallium/drivers/zink/zink_context.c
+++ b/src/gallium/drivers/zink/zink_context.c
@@ -535,11 +535,11 @@
                        struct pipe_sampler_view **views)
 {
    struct zink_context *ctx = zink_context(pctx);
-   assert(views);
    for (unsigned i = 0; i < num_views; ++i) {
+      struct pipe_sampler_view *pview = views ? views[i] : NULL;
       pipe_sampler_view_reference(
          &ctx->image_views[shader_type][start_slot + i],
-         views[i]);
+         pview);
    }
    ctx->num_image_views[shader_type] = start_slot + num_views;
 }