ARM: shmobile: koelsch-reference: Remove duplicate CCF initialization

The common clock framework is initialized in the rcar_gen2_init_timer()
function, remove the of_clk_init() call.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>