dmaengine: imx-sdma: Fix: Remove 'always true' comparison

event_id0 is defined as 'unsigned int', so it is always greater or
equal to zero.

Remove the unneeded comparisons to fix the following W=1 build
warning:

drivers/dma/imx-sdma.c: In function 'sdma_free_chan_resources':
drivers/dma/imx-sdma.c:1334:23: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
1334 |  if (sdmac->event_id0 >= 0)
|                       ^~
drivers/dma/imx-sdma.c: In function 'sdma_config':
drivers/dma/imx-sdma.c:1635:23: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
1635 |  if (sdmac->event_id0 >= 0) {
|

Fixes: 25962e1a ("dmaengine: imx-sdma: Fix the event id check to include RX event for UART6")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Link: https://lore.kernel.org/r/20200621155730.28766-1-festevam@gmail.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/imx-sdma.c

@@ -1331,8 +1331,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
 
 	sdma_channel_synchronize(chan);
 
-	if (sdmac->event_id0 >= 0)
-		sdma_event_disable(sdmac, sdmac->event_id0);
+	sdma_event_disable(sdmac, sdmac->event_id0);
 	if (sdmac->event_id1)
 		sdma_event_disable(sdmac, sdmac->event_id1);
 
@@ -1632,11 +1631,9 @@ static int sdma_config(struct dma_chan *chan,
 	memcpy(&sdmac->slave_config, dmaengine_cfg, sizeof(*dmaengine_cfg));
 
 	/* Set ENBLn earlier to make sure dma request triggered after that */
-	if (sdmac->event_id0 >= 0) {
-		if (sdmac->event_id0 >= sdmac->sdma->drvdata->num_events)
-			return -EINVAL;
-		sdma_event_enable(sdmac, sdmac->event_id0);
-	}
+	if (sdmac->event_id0 >= sdmac->sdma->drvdata->num_events)
+		return -EINVAL;
+	sdma_event_enable(sdmac, sdmac->event_id0);
 
 	if (sdmac->event_id1) {
 		if (sdmac->event_id1 >= sdmac->sdma->drvdata->num_events)