dmaengine: dw: don't handle interrupt when dmaengine is not used

When dma controller is not used by any user and set off,
we should disble interrupt handler, at least the interrupt
reset part, for some subsystem, e.g. ADSP, may use the
dma in its own logic, here reset the interrupt may make
this subsystem work abnormally.

Signed-off-by: Jie Yang <yang.jie@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 455b7a4..a8ad052 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -626,7 +626,7 @@
 	dev_vdbg(dw->dma.dev, "%s: status=0x%x\n", __func__, status);
 
 	/* Check if we have any interrupt from the DMAC */
-	if (!status)
+	if (!status || !dw->in_use)
 		return IRQ_NONE;
 
 	/*