LF-4273-2 gpio: vf610: clarify the content of GPIO labels

The label of GPIO is all "vf610-gpio" in rootfs before.
Use its module name to fill the GPIO labels. So that we can distinguish
them more conveniently in rootfs.

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Reviewed-by: Haibo Chen <haibo.chen@nxp.com>