ARM: mach-shmobile: sh73a0 map_io and init_early update

Update the sh73a0 SoC and the AG5EVM and Kota2 boards to make use
of the functions sh73a0_map_io() and sh73a0_add_early_devices().

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>