ARM: shmobile: Rename to r8a73a4_init_early()

Rename r8a73a4_init_delay() into r8a73a4_init_early()
to make the function name show that more than just
delay setup may happen in the future.

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