tests: dma: Initialise callback enable flags

The test failed to initilise these to known states, so fix this by
asking for end of transfer and error callbacks.

Change-Id: I523168381329062ec0c17aa41cb4033b78d8ed99
Signed-off-by: Jon Medhurst <[email protected]>

Author: tixy

tests/drivers/dma/test_chan_blen_transfer/src/test_dma.c

@@ -55,6 +55,8 @@ static int test_task(uint32_t chan_id, uint32_t blen)
 	dma_cfg.source_burst_length = blen;
 	dma_cfg.dest_burst_length = blen;
 	dma_cfg.dma_callback = test_done;
+	dma_cfg.complete_callback_en = 0;
+	dma_cfg.error_callback_en = 1;
 	dma_cfg.block_count = 1;
 	dma_cfg.head_block = &dma_block_cfg;