v3dv: drop unused field from v3dv_cmd_buffer

Not needed since we moved to the common sync framework.

Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Part-of: <!20787>

src/broadcom/vulkan/v3dv_cmd_buffer.c

@@ -66,7 +66,6 @@ cmd_buffer_init(struct v3dv_cmd_buffer *cmd_buffer,
 
    list_inithead(&cmd_buffer->private_objs);
    list_inithead(&cmd_buffer->jobs);
-   list_inithead(&cmd_buffer->list_link);
 
    cmd_buffer->state.subpass_idx = -1;
    cmd_buffer->state.meta.subpass_idx = -1;

src/broadcom/vulkan/v3dv_private.h

@@ -1709,12 +1709,6 @@ struct v3dv_cmd_buffer {
 
    struct v3dv_device *device;
 
-   /* Used at submit time to link command buffers in the submission that have
-    * spawned wait threads, so we can then wait on all of them to complete
-    * before we process any signal semaphores or fences.
-    */
-   struct list_head list_link;
-
    VkCommandBufferUsageFlags usage_flags;
 
    enum v3dv_cmd_buffer_status status;