spi: spi-au1550: replace ternary operator with min()

Fix the following coccicheck warnings:

drivers/spi/spi-au1550.c:408:21-22: WARNING opportunity for min()
drivers/spi/spi-au1550.c:542:21-22: WARNING opportunity for min()

min() macro is defined in include/linux/minmax.h. It avoids multiple
evaluations of the arguments when non-constant and performs strict
type-checking.
Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com>
Link: https://lore.kernel.org/r/20220513130333.58379-1-guozhengkui@vivo.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-au1550.c

@@ -405,7 +405,7 @@ static int au1550_spi_dma_txrxb(struct spi_device *spi, struct spi_transfer *t)
 		dma_unmap_single(hw->dev, dma_tx_addr, t->len,
 			DMA_TO_DEVICE);
 
-	return hw->rx_count < hw->tx_count ? hw->rx_count : hw->tx_count;
+	return min(hw->rx_count, hw->tx_count);
 }
 
 static irqreturn_t au1550_spi_dma_irq_callback(struct au1550_spi *hw)
@@ -539,7 +539,7 @@ static int au1550_spi_pio_txrxb(struct spi_device *spi, struct spi_transfer *t)
 
 	wait_for_completion(&hw->master_done);
 
-	return hw->rx_count < hw->tx_count ? hw->rx_count : hw->tx_count;
+	return min(hw->rx_count, hw->tx_count);
 }
 
 static irqreturn_t au1550_spi_pio_irq_callback(struct au1550_spi *hw)