rockchip: add text_offset to kernel_addr_r on aarch64 platforms

rockchip: add text_offset to kernel_addr_r on aarch64 platforms

Booting a aarch64 Linux kernel requires the image to be placed
text_offset bytes from a 2MB aligned address.
See https://www.kernel.org/doc/Documentation/arm64/booting.txt

booti_setup() takes care about this alignment and will relocate the
image if not properly aligned with memmove(). This can require up
to double the size of the loaded image and therefore accidentally
overwrite content placed there (i.e ramdisk_addr_r) for large kernel
images.

By adding text_offset to the default kernel_addr_r we can prevent that
from happening for kernels larger 18MB and also save a few cycles.

We can assume a text_offset of 0x80000 for most cases, all others will be
handled by booti_setup() anyway.

Signed-off-by: Klaus Goger <klaus.goger@theobroma-systems.com>
Acked-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>