drm/i915/selftest: Fix potential memory leak

Object out is not released on path that no VMA instance found. The root
cause is jumping to an unexpected label on the error path.

Fixes: a47e788c ("drm/i915/selftests: Exercise CS TLB invalidation")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20210122015640.16002-1-bianpan2016@163.com
(cherry picked from commit 2b015017d5cb01477a79ca184ac25c247d664568)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/selftests/i915_gem_gtt.c

@@ -1880,7 +1880,7 @@ static int igt_cs_tlb(void *arg)
 	vma = i915_vma_instance(out, vm, NULL);
 	if (IS_ERR(vma)) {
 		err = PTR_ERR(vma);
-		goto out_put_batch;
+		goto out_put_out;
 	}
 
 	err = i915_vma_pin(vma, 0, 0,