drivers: depend on HAS_IOMEM for devm_platform_ioremap_resource()

We only build devm_ioremap_resource() if HAS_IOMEM is selected, so this
dependency must cascade down to devm_platform_ioremap_resource().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/base/platform.c

@@ -87,6 +87,7 @@ EXPORT_SYMBOL_GPL(platform_get_resource);
  *        resource managemend
  * @index: resource index
  */
+#ifdef CONFIG_HAS_IOMEM
 void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
 					     unsigned int index)
 {
@@ -96,6 +97,7 @@ void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
 	return devm_ioremap_resource(&pdev->dev, res);
 }
 EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
+#endif /* CONFIG_HAS_IOMEM */
 
 /**
  * platform_get_irq - get an IRQ for a device