mtd: nand: pxa3xx: Use of_machine_is_compatible()

This patch replaces cpu_is_pxa3xx() with of_machine_is_compatible()
which allows to build this driver for other platforms than ARCH_PXA.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Nikita Kiryanov <nikita@compulab.co.il>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
Reviewed-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/nand/pxa3xx_nand.c

@@ -1094,7 +1094,7 @@ static int alloc_nand_resource(struct platform_device *pdev)
 	 * bindings. It can be removed once we have a prober DMA controller
 	 * framework for DT.
 	 */
-	if (pdev->dev.of_node && cpu_is_pxa3xx()) {
+	if (pdev->dev.of_node && of_machine_is_compatible("marvell,pxa3xx")) {
 		info->drcmr_dat = 97;
 		info->drcmr_cmd = 99;
 	} else {