panfrost: Raise TEXTURE_BUFFER_OFFSET_ALIGNMENT

The blob advertises 64 for this, so let's use the same value. Small
alignments are observed to raise an IMPRECISE_FAULT at least on Bifrost.
As a bonus this forces cache line alignment which will help perf. Fixes

dEQP-GLES31.functional.texture.texture_buffer.render.as_vertex_texture.offset_1_alignments

Fixes: 5f7bafa316 ("panfrost: Enable ARB_texture_buffer_object")
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9164>
(cherry picked from commit 3f21b089f8)

.pick_status.json

@@ -2596,7 +2596,7 @@
         "description": "panfrost: Raise TEXTURE_BUFFER_OFFSET_ALIGNMENT",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "master_sha": null,
         "because_sha": "5f7bafa316f60ff79b9839cf88142b33f330a8e7"
     },

src/gallium/drivers/panfrost/pan_screen.c

@@ -192,8 +192,9 @@ panfrost_get_param(struct pipe_screen *screen, enum pipe_cap param)
         case PIPE_CAP_MAX_TEXTURE_BUFFER_SIZE:
                 return 65536;
 
+        /* Must be at least 64 for correct behaviour */
         case PIPE_CAP_TEXTURE_BUFFER_OFFSET_ALIGNMENT:
-                return 16;
+                return 64;
 
         case PIPE_CAP_QUERY_TIMESTAMP:
                 return is_gl3;