linux-phytec-ti

Documentation: clock: fixed-clock: Remove unsupported 'gpios' property

Remove the 'gpios' property from the documentation as this is something that the
current fixed clock driver does not handle.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>