A similar situation as described previously with pnv_phb3_root_port
devices also happens with pnv_phb4_root_ports.

The solution is the same: assign an unique chassis/slot combo for them.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220105212338.49899-3-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>