tu/lrz: Fix multiple subpass case with secondaries

In
dEQP-VK.renderpass.dedicated_allocation.attachment_allocation.input_output.94
we have the following:

- There is more than one subpass, but only one depth attachment.
- The first subpass doesn't use depth.
- The subpass that does use depth has a draw call in a secondary.

We wouldn't hit the case where there's more than one depth attachment,
but because tu_begin_resumed_renderpass() only looked at the first
subpass it wouldn't find the depth attachment and would leave LRZ
invalid and thus a NULL LRZ fast-clear base. Then
tu_begin_secondary_cmdbuf() would leave LRZ enabled and the draw would
have LRZ enabled, leading to a hang.

Fix this by making tu_begin_resumed_renderpass() match
tu_begin_renderpass() with how it finds the depth attachment.

Fixes: 4b5f0d98 ("tu: Overhaul LRZ, implement on-GPU dir tracking and LRZ fast-clear")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18369>

src/freedreno/vulkan/tu_lrz.c

@@ -271,8 +271,14 @@ tu_lrz_begin_resumed_renderpass(struct tu_cmd_buffer *cmd,
 {
     /* Track LRZ valid state */
    memset(&cmd->state.lrz, 0, sizeof(cmd->state.lrz));
-   uint32_t a = cmd->state.subpass->depth_stencil_attachment.attachment;
-   if (a != VK_ATTACHMENT_UNUSED) {
+
+   uint32_t a;
+   for (a = 0; a < cmd->state.pass->attachment_count; a++) {
+      if (cmd->state.attachments[a]->image->lrz_height)
+         break;
+   }
+
+   if (a != cmd->state.pass->attachment_count) {
       const struct tu_render_pass_attachment *att = &cmd->state.pass->attachments[a];
       tu_lrz_init_state(cmd, att, cmd->state.attachments[a]);
       if (att->clear_mask & (VK_IMAGE_ASPECT_COLOR_BIT | VK_IMAGE_ASPECT_DEPTH_BIT)) {