spi: sg2044-nor: fix signedness bug in sg2044_spifmc_write()

The "ret" variable needs to be signed for the error handling to work.
It should be type int, since it only holds zero and negative error
codes.

Fixes: de16c32 ("spi: sophgo: add SG2044 SPI NOR controller driver")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://patch.msgid.link/4e16e1bf-e5fb-4771-bc92-c5cba9aac473@stanley.mountain
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Dan Carpenter

drivers/spi/spi-sg2044-nor.c

@@ -216,7 +216,7 @@ static ssize_t sg2044_spifmc_write(struct sg2044_spifmc *spifmc,
 	size_t xfer_size;
 	const u8 *dout = op->data.buf.out;
 	int i, offset;
-	size_t ret;
+	int ret;
 	u32 reg;
 
 	reg = sg2044_spifmc_init_reg(spifmc);