openeuler_defconfig: enable iocost in openeuler_defconfig for x86 and arm64

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8ND38



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Set CONFIG_BLK_CGROUP_IOCOST=y, CONFIG_BLK_CGROUP_LEGACY_IOCOST=y,
CONFIG_BLK_RQ_ALLOC_TIME=y in openeuler_defconfig for x86 and arm64.

Signed-off-by: Li Nan <linan122@huawei.com>