uboot-imx

fdt: Add a do_fixup_by_path_string() function

The do_fixup_by_path_string() will set the specified node's property to the
value contained in "status". It would just be an inline wrapper for
do_fixup_by_path() that calls strlen on the argument.

Signed-off-by: Chunhe Lan <Chunhe.Lan@freescale.com>