mtd: spi-nor: intel: use ERR_CAST in return statement

This fixes a sparse warning about incorrect type in return expression.
Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>

drivers/mtd/spi-nor/intel-spi.c

@@ -728,7 +728,7 @@ struct intel_spi *intel_spi_probe(struct device *dev,
 
 	ispi->base = devm_ioremap_resource(dev, mem);
 	if (IS_ERR(ispi->base))
-		return ispi->base;
+		return ERR_CAST(ispi->base);
 
 	ispi->dev = dev;
 	ispi->info = info;