ARM: shmobile: r8a7790: add __initdata on resource and device data

These data will be kmemdup()'ed on
platform_device_add_resources() and platform_device_add_data()
This patch removed "const" to avoid section type conflict
with r8a7790_boards_compat_dt

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>