Please replace the line save_config ${PN}.conf in sys-kernel/linux-firmware's src_install() by use savedconfig || save_config ${PN}.conf Re-saving the config in this situation is useless, and if one keeps the configuration in a version-agnostic savedconfig/sys-kernel/linux-firmware file, every new version of linux-firmware currently creates its own linux-firmware-200xxxx duplicate.
Ping.
Reassigning to chitanh, who appears to be the only active maintainer of this package.
Fixed in linux-firmware-20160223