ARM: shmobile: r8a7778: Stop passing mode pins state to clock driver

Now the R-Car M1A CPG clock driver obtains the state of the mode pins
from the R-Car RST driver, there's no longer a need to pass this state
explicitly. Hence we can just remove the .init_time() callback, the
generic ARM code will take care of calling of_clk_init().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Dirk Behme <dirk.behme@de.bosch.com>