spi: spi-pxa2xx: Remove unused legacy null dma buffer and allocation for it

Remove null_dma_buf variable and extra allocation for it. It is not needed
since commit 6356437e ("spi: spi-pxa2xx: remove legacy PXA DMA bits").
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-pxa2xx.c

@@ -1414,8 +1414,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	/* Allocate master with space for drv_data and null dma buffer */
-	master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
+	master = spi_alloc_master(dev, sizeof(struct driver_data));
 	if (!master) {
 		dev_err(&pdev->dev, "cannot alloc spi_master\n");
 		pxa_ssp_free(ssp);
@@ -1442,7 +1441,6 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
 	master->auto_runtime_pm = true;
 
 	drv_data->ssp_type = ssp->type;
-	drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT);
 
 	drv_data->ioaddr = ssp->mmio_base;
 	drv_data->ssdr_physical = ssp->phys_base + SSDR;

drivers/spi/spi-pxa2xx.h

@@ -36,9 +36,6 @@ struct driver_data {
 	/* PXA hookup */
 	struct pxa2xx_spi_master *master_info;
 
-	/* PXA private DMA setup stuff */
-	u32 *null_dma_buf;
-
 	/* SSP register addresses */
 	void __iomem *ioaddr;
 	u32 ssdr_physical;