drm/st7586: Avoid spamming logs if probe is deferred

The GPIO request can fail and probe may be deferred. Thus,
the error message may be printed again and again. Avoid
this by replacing DRM_DEV_ERROR() by dev_err_probe().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210421163157.50949-2-andriy.shevchenko@linux.intel.com

drivers/gpu/drm/tiny/st7586.c

@@ -323,16 +323,12 @@ static int st7586_probe(struct spi_device *spi)
 	bufsize = (st7586_mode.vdisplay + 2) / 3 * st7586_mode.hdisplay;
 
 	dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
-	if (IS_ERR(dbi->reset)) {
-		DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
-		return PTR_ERR(dbi->reset);
-	}
+	if (IS_ERR(dbi->reset))
+		return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get GPIO 'reset'\n");
 
 	a0 = devm_gpiod_get(dev, "a0", GPIOD_OUT_LOW);
-	if (IS_ERR(a0)) {
-		DRM_DEV_ERROR(dev, "Failed to get gpio 'a0'\n");
-		return PTR_ERR(a0);
-	}
+	if (IS_ERR(a0))
+		return dev_err_probe(dev, PTR_ERR(a0), "Failed to get GPIO 'a0'\n");
 
 	device_property_read_u32(dev, "rotation", &rotation);