uboot-imx

core: Make device_is_compatible live-tree compatible

Judging from its name and parameters, device_is_compatible looks like it
is compatible with a live device tree, but it actually isn't.

Make it compatible with a live device tree.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Mario Six <mario.six@gdsys.cc>