platform/chrome: cros_ec_spi: Wait for USECS, not NSECS

The use of `delay_usecs` in terminate_request() was replaced with the new
`delay` struct used by the SPI subsystem, however the unit was
set to SPI_DELAY_UNIT_NSECS instead of SPI_DELAY_UNIT_USECS. This fixes that.

Fixes: 7d3ca507 ("platform/chrome: cros_ec_spi: Use new structure for SPI transfer delays")
Signed-off-by: Benson Leung <bleung@chromium.org>

drivers/platform/chrome/cros_ec_spi.c

@@ -128,7 +128,7 @@ static int terminate_request(struct cros_ec_device *ec_dev)
 	spi_message_init(&msg);
 	memset(&trans, 0, sizeof(trans));
 	trans.delay.value = ec_spi->end_of_msg_delay;
-	trans.delay.unit = SPI_DELAY_UNIT_NSECS;
+	trans.delay.unit = SPI_DELAY_UNIT_USECS;
 	spi_message_add_tail(&trans, &msg);
 
 	ret = spi_sync_locked(ec_spi->spi, &msg);