sf: winbond: fix page_size

Commit a4ed3b65 "sf: inline data constants" modified winbond.c's page_size
from 256 to 4096. This prevents either/both of "sf write" writing the
correct data, or "sf read" from reading the correct data back.

This allows U-Boot running on Compulab Tegra to upgrade itself.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

drivers/mtd/spi/winbond.c

@@ -99,7 +99,7 @@ struct spi_flash *spi_flash_probe_winbond(struct spi_slave *spi, u8 *idcode)
 	flash->write = spi_flash_cmd_write_multi;
 	flash->erase = spi_flash_cmd_erase;
 	flash->read = spi_flash_cmd_read_fast;
-	flash->page_size = 4096;
+	flash->page_size = 256;
 	flash->sector_size = 4096;
 	flash->size = 4096 * 16 * params->nr_blocks;