lavapipe: fix pipeline vp/scissor mixup.

Not copying all the scissors caused
dEQP-VK.pipeline.extended_dynamic_state.two_draws_dynamic.2_viewports
to fail but thah test pointlessly relies on KHR_multiview (cts issue
filed).

Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Fixes: b38879f8c5 ("vallium: initial import of the vulkan frontend")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9422>

src/gallium/frontends/lavapipe/lvp_pipeline.c

@@ -214,7 +214,7 @@ deep_copy_viewport_state(void *mem_ctx,
       LVP_PIPELINE_DUP(dst->pScissors,
                        src->pScissors,
                        VkRect2D,
-                       src->viewportCount);
+                       src->scissorCount);
    } else
       dst->pScissors = NULL;
    dst->scissorCount = src->scissorCount;