dmaengine: ipu: Use irq_desc_get_xxx() to avoid redundant lookup of irq_desc

Use irq_desc_get_xxx() to avoid redundant lookup of irq_desc while we
already have a pointer to corresponding irq_desc.

This is also a preparation for the removal of the 'irq' argument from
interrupt flow handlers.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/ipu/ipu_irq.c

@@ -268,7 +268,7 @@ int ipu_irq_unmap(unsigned int source)
 /* Chained IRQ handler for IPU error interrupt */
 static void ipu_irq_err(unsigned int irq, struct irq_desc *desc)
 {
-	struct ipu *ipu = irq_get_handler_data(irq);
+	struct ipu *ipu = irq_desc_get_handler_data(desc);
 	u32 status;
 	int i, line;