spi: spi-fsl-dspi: LS2080A and LX2160A support XSPI mode

XSPI allows for 2 extra features:
- Command cycling (use a single TX command with more than 1 word in the
  TX FIFO).
- Increased word size (from 16 bits to 32 bits)

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Message-Id: <20200302001958.11105-5-olteanv@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-fsl-dspi.c

@@ -179,6 +179,7 @@ static const struct fsl_dspi_devtype_data devtype_data[] = {
 		.trans_mode		= DSPI_TCFQ_MODE,
 		.max_clock_factor	= 8,
 		.ptp_sts_supported	= true,
+		.xspi_mode		= true,
 		.fifo_size		= 4,
 	},
 	[LS2085A] = {
@@ -191,6 +192,7 @@ static const struct fsl_dspi_devtype_data devtype_data[] = {
 		.trans_mode		= DSPI_TCFQ_MODE,
 		.max_clock_factor	= 8,
 		.ptp_sts_supported	= true,
+		.xspi_mode		= true,
 		.fifo_size		= 4,
 	},
 	[MCF5441X] = {