spi: rspi: remove slave_id settings for DMAEngine

Current rspi sets dma_slave_config :: slave_id field for DMAEngine,
but it is no longer needed. Let's remove it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/spi/spi-rspi.c

@@ -913,7 +913,6 @@ static struct dma_chan *rspi_request_dma_chan(struct device *dev,
 	}
 
 	memset(&cfg, 0, sizeof(cfg));
-	cfg.slave_id = id;
 	cfg.direction = dir;
 	if (dir == DMA_MEM_TO_DEV) {
 		cfg.dst_addr = port_addr;