spi: dw: Use spi_bpw_to_bytes() helper

Use existing helper to get amount of bytes (as power-of-two value)
from bits per word.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20250417152529.490582-3-andriy.shevchenko@linux.intel.com
Acked-by: Mukesh Kumar Savaliya <quic_msavaliy@quicinc.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: andy-shev

drivers/spi/spi-dw-core.c

@@ -423,7 +423,7 @@ static int dw_spi_transfer_one(struct spi_controller *host,
 	int ret;
 
 	dws->dma_mapped = 0;
-	dws->n_bytes = roundup_pow_of_two(BITS_TO_BYTES(transfer->bits_per_word));
+	dws->n_bytes = spi_bpw_to_bytes(transfer->bits_per_word);
 	dws->tx = (void *)transfer->tx_buf;
 	dws->tx_len = transfer->len / dws->n_bytes;
 	dws->rx = transfer->rx_buf;