rpi: Change load addresses to make more room for the kernel & DTB

rpi: Change load addresses to make more room for the kernel & DTB

As of Linux 4.16, a multiplatform AArch64 kernel with our distro config
takes 26M. The current space reservation leaves only 17M for the kernel
and if it goes over it, the initrd gets overwritten when loading the
kernel from the filesystem.

A similar problem happens on ARMv7 with the DTBs taken from the
downstream Raspberry Pi foundation kernel. I guess they compile them
with DT overlay support enabled which grows them just enough.

Fix both of these problems by rewriting the memory map, which now allows
kernels to be up to 36M and DTBs up to 1M. Also the comment block was
kind of obsolete ever since the introduction of AArch64 support and the
firmware-loaded DTB doesn't get placed at 0x100 anymore either, so that
is fixed as well.

Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com>
Signed-off-by: Alexander Graf <agraf@suse.de>