spi: spi-cadence: add support for chip select high

The spi cadence driver should support spi-cs-high in mode bits
so that the peripherals that needs the chip select to be high active can
use it. Add the SPI-CS-HIGH flag in the supported mode bits.
Signed-off-by: Shreyas Joshi <shreyas.joshi@biamp.com>
Link: https://lore.kernel.org/r/20200710211655.1564-1-shreyas.joshi@biamp.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-cadence.c

@@ -556,7 +556,7 @@ static int cdns_spi_probe(struct platform_device *pdev)
 	master->unprepare_transfer_hardware = cdns_unprepare_transfer_hardware;
 	master->set_cs = cdns_spi_chipselect;
 	master->auto_runtime_pm = true;
-	master->mode_bits = SPI_CPOL | SPI_CPHA;
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 
 	/* Set to default valid value */
 	master->max_speed_hz = clk_get_rate(xspi->ref_clk) / 4;