tu/autotune: Always prefer GMEM with fragment density maps

If we encounter an app doing bad things where we want sysmem, we can fix
that later, but this seems like the right thing to do initially.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20304>

src/freedreno/vulkan/tu_autotune.cc

@@ -535,6 +535,17 @@ tu_autotune_use_bypass(struct tu_autotune *at,
    if (cmd_buffer->state.rp.sysmem_single_prim_mode)
       return false;
 
+   /* If the user is using a fragment density map, then this will cause less
+    * FS invocations with GMEM, which has a hard-to-measure impact on
+    * performance because it depends on how heavy the FS is in addition to how
+    * many invocations there were and the density. Let's assume the user knows
+    * what they're doing when they added the map, because if sysmem is
+    * actually faster then they could've just not used the fragment density
+    * map.
+    */
+   if (pass->has_fdm)
+      return false;
+
    /* For VK_COMMAND_BUFFER_USAGE_SIMULTANEOUS_USE_BIT buffers
     * we would have to allocate GPU memory at the submit time and copy
     * results into it.