ASoC: SOF: loader: fix memory leak in get_ext_windows

sdev->info_window is allocated with kmemdup and never freed, use devm_
version since this is only used for first boot.

Fixes: 8d809c15 ('ASoC: SOF: ext_manifest: parse windows')
Cc: Karol Trzcinski <karolx.trzcinski@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Daniel Baluta <daniel.baluta@gmail.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20200825235854.1588034-3-ranjani.sridharan@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/loader.c

@@ -33,7 +33,8 @@ static int get_ext_windows(struct snd_sof_dev *sdev,
 	}
 
 	/* keep a local copy of the data */
-	sdev->info_window = kmemdup(w, ext_hdr->hdr.size, GFP_KERNEL);
+	sdev->info_window = devm_kmemdup(sdev->dev, w, ext_hdr->hdr.size,
+					 GFP_KERNEL);
 	if (!sdev->info_window)
 		return -ENOMEM;