This commit moves the Orion5x platforms using the Device Tree to use
the recently introduced clock driver for Orion5x. To achieve that, it:

 * Adds the necessary DT description of the clock.

 * Selects ORION_CLK to enable the compilation of the clock driver.

 * Call of_clk_init() instead of the Orion5x-specific clock
   initialization function.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1398202002-28530-21-git-send-email-thomas.petazzoni@free-electrons.comAcked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>