md/raid1: enable io accounting

mainline inclusion
from mainline-v5.14-rc1
commit a0159832
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I587H6
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a0159832e51e3af03b89ecc5d6b9db451e529b5f



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For raid1, we record the start time between split bio and clone bio,
and finish the accounting in the final endio.

Also introduce start_time in r1bio accordingly.

Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
Conflict:
	drivers/md/raid1.c
Signed-off-by: Zhang Wensheng <zhangwensheng5@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>