sf: winbond: Add support for the Winbond W25X40

The Winbond W25X40 is now being used in the IP02 (and possibly IP04).
Tested and working on the actual device.
diff --git a/drivers/mtd/spi/winbond.c b/drivers/mtd/spi/winbond.c
index 45bd146..a6a6653 100644
--- a/drivers/mtd/spi/winbond.c
+++ b/drivers/mtd/spi/winbond.c
@@ -36,6 +36,14 @@
 
 static const struct winbond_spi_flash_params winbond_spi_flash_table[] = {
 	{
+		.id			= 0x3013,
+		.l2_page_size		= 8,
+		.pages_per_sector	= 16,
+		.sectors_per_block	= 16,
+		.nr_blocks		= 8,
+		.name			= "W25X40",
+	},
+	{
 		.id			= 0x3015,
 		.l2_page_size		= 8,
 		.pages_per_sector	= 16,