roda/rk9: Drop MAX_PHYSICAL_CPUS

Change-Id: I9c41cccf9058c48006b247aca705a3f869ae82a6
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5524
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>