[media] atmel-isi: Protect PM-only functions to kill warning

If CONFIG_PM=n:

    drivers/media/platform/soc_camera/atmel-isi.c:1044: warning: 'atmel_isi_runtime_suspend' defined but not used
    drivers/media/platform/soc_camera/atmel-isi.c:1054: warning: 'atmel_isi_runtime_resume' defined but not used

Protect the unused functions by #ifdef CONFIG_PM to fix this.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Josh Wu <josh.wu@atmel.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/soc_camera/atmel-isi.c

@@ -1040,6 +1040,7 @@ static int atmel_isi_probe(struct platform_device *pdev)
 	return ret;
 }
 
+#ifdef CONFIG_PM
 static int atmel_isi_runtime_suspend(struct device *dev)
 {
 	struct soc_camera_host *soc_host = to_soc_camera_host(dev);
@@ -1058,6 +1059,7 @@ static int atmel_isi_runtime_resume(struct device *dev)
 
 	return clk_prepare_enable(isi->pclk);
 }
+#endif /* CONFIG_PM */
 
 static const struct dev_pm_ops atmel_isi_dev_pm_ops = {
 	SET_RUNTIME_PM_OPS(atmel_isi_runtime_suspend,