configs: ti_armv7_keystone2: fix initrd address at args_ramfs

This patch set the correct initrd address to much rdaddr, which used at
get_fs_ramfs commad.

Fixes: 3e97f0b63c8e ("configs: ti_armv7_keystone2: switch addresses
to generic addresses")

Signed-off-by: Vitaly Andrianov <vitalya@ti.com>