spi: armada-3700: use 'time_left' variable with wait_for_completion_timeout()

There is a confusing pattern in the kernel to use a variable named 'timeout' to
store the result of wait_for_completion_timeout() causing patterns like:

	timeout = wait_for_completion_timeout(...)
	if (!timeout) return -ETIMEDOUT;

with all kinds of permutations. Use 'time_left' as a variable to make the code
self explaining.

Fix to the proper variable type 'unsigned long' while here.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20240430114142.28551-2-wsa+renesas@sang-engineering.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-armada-3700.c

@@ -339,7 +339,7 @@ static irqreturn_t a3700_spi_interrupt(int irq, void *dev_id)
 static bool a3700_spi_wait_completion(struct spi_device *spi)
 {
 	struct a3700_spi *a3700_spi;
-	unsigned int timeout;
+	unsigned long time_left;
 	unsigned int ctrl_reg;
 	unsigned long timeout_jiffies;
 
@@ -361,12 +361,12 @@ static bool a3700_spi_wait_completion(struct spi_device *spi)
 		     a3700_spi->wait_mask);
 
 	timeout_jiffies = msecs_to_jiffies(A3700_SPI_TIMEOUT);
-	timeout = wait_for_completion_timeout(&a3700_spi->done,
-					      timeout_jiffies);
+	time_left = wait_for_completion_timeout(&a3700_spi->done,
+						timeout_jiffies);
 
 	a3700_spi->wait_mask = 0;
 
-	if (timeout)
+	if (time_left)
 		return true;
 
 	/* there might be the case that right after we checked the