dma: edma.c: remove edma_desc leakage

Free memory allocated to edma_desc when failing to allocate slot.

Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
index 098a8da..3519111 100644
--- a/drivers/dma/edma.c
+++ b/drivers/dma/edma.c
@@ -306,6 +306,7 @@
 						EDMA_SLOT_ANY);
 			if (echan->slot[i] < 0) {
 				dev_err(dev, "Failed to allocate slot\n");
+				kfree(edesc);
 				return NULL;
 			}
 		}