airoha: adjust and default the loadaddr

airoha: adjust and default the loadaddr

Similar to e92b153e99 ("mediatek: introduce KERNEL_LOADADDR to Device/Default template"),
let's move the default loadaddr to Device/Default.

What's more, use 0x80200000 instead of the SDK default value 0x80088000
to avoid the following error which may overwrite TZ memory and cause crash:

    [    0.000000] [Firmware Bug]: Kernel image misaligned at boot, please fix your bootloader!
    [    0.000000] OF: reserved mem: Reserved memory: failed to reserve memory for node 'atf@80000000': base 0x0000000080000000, size 2 MiB

Signed-off-by: Ziyang Huang <hzyitc@outlook.com>
[ fix spelling mistake ]
Link: https://github.com/openwrt/openwrt/pull/20470
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>