dmaengine: pxa_dma: remove redundant irqsave and irqrestore in hardIRQ

Running in hardIRQ, disabling IRQ is redundant since hardIRQ has disabled
IRQ. This patch removes the irqsave and irqstore to save some instruction
cycles.

Signed-off-by: Barry Song <[e-mail]>
Acked-by: Robert Jarzmik <[e-mail]>
Cc: Daniel Mack <[e-mail]>
Cc: Haojian Zhuang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/pxa_dma.c

···
 	struct pxad_chan *chan = phy->vchan;
 	struct virt_dma_desc *vd, *tmp;
 	unsigned int dcsr;
-	unsigned long flags;
 	bool vd_completed;
 	dma_cookie_t last_started = 0;
 
···
 	if (dcsr & PXA_DCSR_RUN)
 		return IRQ_NONE;
 
-	spin_lock_irqsave(&chan->vc.lock, flags);
+	spin_lock(&chan->vc.lock);
 	list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
 		vd_completed = is_desc_completed(vd);
 		dev_dbg(&chan->vc.chan.dev->device,
···
 			pxad_launch_chan(chan, to_pxad_sw_desc(vd));
 		}
 	}
-	spin_unlock_irqrestore(&chan->vc.lock, flags);
+	spin_unlock(&chan->vc.lock);
 	wake_up(&chan->wq_state);
 
 	return IRQ_HANDLED;