spi: pxa2xx: Add missed security checks

pxa2xx_spi_init_pdata misses checks for devm_clk_get and
platform_get_irq.
Add checks for them to fix the bugs.

Since ssp->clk and ssp->irq are used in probe, they are mandatory here.
So we cannot use _optional() for devm_clk_get and platform_get_irq.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Link: https://lore.kernel.org/r/20191109080943.30428-1-hslester96@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-pxa2xx.c

@@ -1557,7 +1557,13 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev)
 #endif
 
 	ssp->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(ssp->clk))
+		return NULL;
+
 	ssp->irq = platform_get_irq(pdev, 0);
+	if (ssp->irq < 0)
+		return NULL;
+
 	ssp->type = type;
 	ssp->dev = &pdev->dev;
 	ssp->port_id = pxa2xx_spi_get_port_id(&pdev->dev);