md: change the return value type of md_write_start to void

md: change the return value type of md_write_start to void

Commit cc27b0c78c79 ("md: fix deadlock between mddev_suspend() and
md_write_start()") aborted md_write_start() with false when mddev is
suspended, which fixed a deadlock if calling mddev_suspend() with
holding reconfig_mutex(). Since mddev_suspend() now includes
lockdep_assert_not_held(), it no longer holds the reconfig_mutex. This
makes previous abort unnecessary. Now, remove unnecessary abort and
change function return value to void.

Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240525185257.3896201-2-linan666@huaweicloud.com