dma: edma: Fix memory leak

When it fails to allocate a slot, edesc should be free'd before return;

Signed-off-by: Valentin Ilie <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/edma.c

···
 				edma_alloc_slot(EDMA_CTLR(echan->ch_num),
 						EDMA_SLOT_ANY);
 			if (echan->slot[i] < 0) {
+				kfree(edesc);
 				dev_err(dev, "Failed to allocate slot\n");
 				kfree(edesc);
 				return NULL;