drm/exynos: Fix error value in exynos_drm_crtc_get_by_type()

EPERM is not the correct error value when the driver is not able to get
its resources. Change it to ENODEV.
Reported-by: NRussell King - ARM Linux <linux@armlinux.org.uk>
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_drm_crtc.c

@@ -228,7 +228,7 @@ struct exynos_drm_crtc *exynos_drm_crtc_get_by_type(struct drm_device *drm_dev,
 		if (to_exynos_crtc(crtc)->type == out_type)
 			return to_exynos_crtc(crtc);
 
-	return ERR_PTR(-EPERM);
+	return ERR_PTR(-ENODEV);
 }
 
 int exynos_drm_set_possible_crtcs(struct drm_encoder *encoder,