spi: imx: mx51-ecspi: Fix CONFIGREG delay comment

spi: imx: mx51-ecspi: Fix CONFIGREG delay comment

For (2 * 1000000) / min_speed_hz < 10 to be true in naturals with zero,
the min_speed_hz must be above 200000 (i.e. 200001 rounds down to 9, so
the condition triggers). Update the comment. No functional change.

Fixes: 6fd8b8503a0dc ("spi: spi-imx: Fix out-of-order CS/SCLK operation at low speeds")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Mark Brown <broonie@kernel.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210727160428.7673-1-marex@denx.de
Signed-off-by: Mark Brown <broonie@kernel.org>