soc: fsl: dpio: remove redundant pointer 'priv'

Pointer 'priv' is being assigned but is never used hence it is
redundant and can be removed.

Cleans up clang warning:
variable 'priv' set but not used [-Wunused-but-set-variable]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Li Yang <leoyang.li@nxp.com>

drivers/soc/fsl/dpio/dpio-driver.c

@@ -50,13 +50,10 @@ static void unregister_dpio_irq_handlers(struct fsl_mc_device *dpio_dev)
 
 static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu)
 {
-	struct dpio_priv *priv;
 	int error;
 	struct fsl_mc_device_irq *irq;
 	cpumask_t mask;
 
-	priv = dev_get_drvdata(&dpio_dev->dev);
-
 	irq = dpio_dev->irqs[0];
 	error = devm_request_irq(&dpio_dev->dev,
 				 irq->msi_desc->irq,