uboot-imx

arm/km: speed up i2c access for keymile boards

We don't need 3us delay for our i2c bus. Decrease it to 1us.
It would also be possible to use 100ns in the future, but
currently kirkwood has no ndelay implementation.

Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Cc: Valentin Longchamp <valentin.longchamp@keymile.com>
Cc: Prafulla Wadaskar <prafulla@marvell.com>
Cc: Heiko Schocher <hs@denx.de>
Acked-by: Heiko Schocher <hs@denx.de>