etnaviv: cosmetic etna_resource_alloc fixes

Get rid if the local bo variable, we can just assign it to the pointer
in the etna_resource struct.
Get rid of superfluous clearing of the TS bo pointer, the struct is already
zero initialized.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7367>
diff --git a/src/gallium/drivers/etnaviv/etnaviv_resource.c b/src/gallium/drivers/etnaviv/etnaviv_resource.c
index e2ef97f..bfb470c 100644
--- a/src/gallium/drivers/etnaviv/etnaviv_resource.c
+++ b/src/gallium/drivers/etnaviv/etnaviv_resource.c
@@ -307,15 +307,13 @@
    uint32_t flags = DRM_ETNA_GEM_CACHE_WC;
    if (templat->bind & PIPE_BIND_VERTEX_BUFFER)
       flags |= DRM_ETNA_GEM_FORCE_MMU;
-   struct etna_bo *bo = etna_bo_new(screen->dev, size, flags);
-   if (unlikely(bo == NULL)) {
+
+   rsc->bo = etna_bo_new(screen->dev, size, flags);
+   if (unlikely(!rsc->bo)) {
       BUG("Problem allocating video memory for resource");
       goto free_rsc;
    }
 
-   rsc->bo = bo;
-   rsc->ts_bo = 0; /* TS is only created when first bound to surface */
-
    if (DBG_ENABLED(ETNA_DBG_ZERO)) {
       void *map = etna_bo_map(bo);
       memset(map, 0, size);