spi: txx9: Use transfer speed unconditionally

SPI core validates the transfer speed and defaults to spi->max_speed_hz in
case the transfer speed is not set.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-txx9.c

@@ -181,7 +181,7 @@ static void txx9spi_work_one(struct txx9spi *c, struct spi_message *m)
 		u32 data;
 		unsigned int len = t->len;
 		unsigned int wsize;
-		u32 speed_hz = t->speed_hz ? : spi->max_speed_hz;
+		u32 speed_hz = t->speed_hz;
 		u8 bits_per_word = t->bits_per_word;
 
 		wsize = bits_per_word >> 3; /* in bytes */