ARM: shmobile: Use shmobile_init_delay() on Genmai boards

Adjust Genmai board support to use shmobile_init_delay() together
with r7s72100 CPU Frequency settings from the DTS.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>