remoteproc: imx_rproc: Fix a resource leak in the remove function

'priv->workqueue' is destroyed in the error handling path of the probe but
not in the remove function.

Add the missing call to release some resources.

Cc: stable <stable@vger.kernel.org>
Fixes: 2df70620 ("remoteproc: imx_proc: enable virtio/mailbox")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Tested-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/d28ca94a4031bd7297d47c2164e18885a5a6ec19.1634366546.git.christophe.jaillet@wanadoo.frSigned-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

drivers/remoteproc/imx_rproc.c

@@ -804,6 +804,7 @@ static int imx_rproc_remove(struct platform_device *pdev)
 	clk_disable_unprepare(priv->clk);
 	rproc_del(rproc);
 	imx_rproc_free_mbox(rproc);
+	destroy_workqueue(priv->workqueue);
 	rproc_free(rproc);
 
 	return 0;