Revert "block/bfq-iosched.c: BFQ scheduler tweaks (thanks pkgnex from
Franco's Dev Team)"

This reverts commit 370939a682b8631479d69ed5fd67395307c0a99e.
Revert "block: add BFQv6 again"

This reverts commit 65aa213e49f82284e9eb938b9521110a642fe48c.
configs: remove BFQv6 since it was causing reboots