spi: rockchip: Fix error in getting num-cs property

Get num-cs u32 from dts of_node property rather than u16.
Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
Link: https://lore.kernel.org/r/20220216014028.8123-2-jon.lin@rock-chips.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-rockchip.c

@@ -654,7 +654,7 @@ static int rockchip_spi_probe(struct platform_device *pdev)
 	struct spi_controller *ctlr;
 	struct resource *mem;
 	struct device_node *np = pdev->dev.of_node;
-	u32 rsd_nsecs;
+	u32 rsd_nsecs, num_cs;
 	bool slave_mode;
 
 	slave_mode = of_property_read_bool(np, "spi-slave");
@@ -764,8 +764,9 @@ static int rockchip_spi_probe(struct platform_device *pdev)
 		 * rk spi0 has two native cs, spi1..5 one cs only
 		 * if num-cs is missing in the dts, default to 1
 		 */
-		if (of_property_read_u16(np, "num-cs", &ctlr->num_chipselect))
-			ctlr->num_chipselect = 1;
+		if (of_property_read_u32(np, "num-cs", &num_cs))
+			num_cs = 1;
+		ctlr->num_chipselect = num_cs;
 		ctlr->use_gpio_descriptors = true;
 	}
 	ctlr->dev.of_node = pdev->dev.of_node;