dmaengine/ste_dma40: fix introduced warnings

The compiler nowadays moans about possibly non-assigned variable.
Fix this by default-assigning 0.
Signed-off-by: Philippe Langlais <philippe.langlais@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/ste_dma40.c

@@ -1829,7 +1829,7 @@ d40_get_dev_addr(struct d40_chan *chan, enum dma_data_direction direction)
 {
 	struct stedma40_platform_data *plat = chan->base->plat_data;
 	struct stedma40_chan_cfg *cfg = &chan->dma_cfg;
-	dma_addr_t addr;
+	dma_addr_t addr = 0;
 
 	if (chan->runtime_addr)
 		return chan->runtime_addr;