ARM: shmobile: r8a7779: Update early timer initialisation order

a894fcc2 ("ARM: smp_twd: Divorce smp_twd
from local timer API") altered twd_local_timer_common_register() so that it
may make use of late_timer_init.

This is problematic on marzen with Magnus's recent patch "ARM: shmobile:
marzen: Switch to DT_MACHINE_START" which switches marzen around to enable
USE_OF and thus shmobile_timer_init(), which is registered as
late_time_init by shmobile_earlytimer_init() stops being a no-op.

As a work-around I have updated r8a7779_earlytimer_init() so that
shmobile_earlytimer_init() is called after r8a7779_register_twd().
Or in other words, the shmobile_earlytimer_init() setting of
late_time_init overwrites that of twd_local_timer_common_register().

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Magnus Damm <damm@opensource.se>