drivers: spi: siwx91x: Swap write and read data inside GSPI controller

Swap the write and read data paths within the GSPI controller to ensure
correct data is seen on the SPI lines during 16-bit transfers.

Signed-off-by: Sai Santhosh Malae <Santhosh.Malae@silabs.com>

Author: smalae

drivers/spi/spi_silabs_siwx91x_gspi.c

@@ -176,8 +176,9 @@ static int gspi_siwx91x_config(const struct device *dev, const struct spi_config
 	/*  Update the number of Data Bits */
 	cfg->reg->GSPI_WRITE_DATA2 = SPI_WORD_SIZE_GET(spi_cfg->operation);
 
-	/* Swap the read data inside the GSPI controller it-self */
-	cfg->reg->GSPI_CONFIG2_b.GSPI_RD_DATA_SWAP_MNL_CSN0 = 0;
+	/* Swap the write and read data inside the GSPI controller it-self */
+	cfg->reg->GSPI_CONFIG2_b.GSPI_RD_DATA_SWAP_MNL_CSN0 = 1;
+	cfg->reg->GSPI_CONFIG2_b.GSPI_WR_DATA_SWAP_MNL_CSN0 = 1;
 
 	/* Enable full-duplex mode and manual read/write */
 	cfg->reg->GSPI_CONFIG1_b.SPI_FULL_DUPLEX_EN = 1;