md: remove MD_RECOVERY_ERROR handling and simplify resync_offset update
Following previous patch "md: update curr_resync_completed even when
MD_RECOVERY_INTR is set", 'curr_resync_completed' always equals
'curr_resync' for resync, so MD_RECOVERY_ERROR can be removed.
Also, simplify resync_offset update logic.
Link: https://lore.kernel.org/linux-raid/20260105110300.1442509-8-linan666@huaweicloud.com
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai@fnnas.com>
Signed-off-by: Yu Kuai <yukuai@fnnas.com>