spi: synquacer: Fix timeout handling in synquacer_spi_transfer_one()

wait_for_completion_timeout() never returns a <0 value. It returns either
on timeout or a positive value (at least 1, or number of jiffies left
till timeout)

So, fix the error handling path and return -ETIMEDOUT should a timeout
occur.

Fixes: b0823ee ("spi: Add spi driver for Socionext SynQuacer platform")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Jassi Brar <jaswinder.singh@linaro.org>
Link: https://lore.kernel.org/r/c2040bf3cfa201fd8890cfab14fa5a701ffeca14.1676466072.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-synquacer.c

@@ -472,10 +472,9 @@ static int synquacer_spi_transfer_one(struct spi_master *master,
 		read_fifo(sspi);
 	}
 
-	if (status < 0) {
-		dev_err(sspi->dev, "failed to transfer. status: 0x%x\n",
-			status);
-		return status;
+	if (status == 0) {
+		dev_err(sspi->dev, "failed to transfer. Timeout.\n");
+		return -ETIMEDOUT;
 	}
 
 	return 0;