dt-binding: fsl-lpuart: use exact SoC revision to document binding

use exact SoC revision instead of wildcard describing
to make the binding more clearer.

Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed