md/raid0: Move queue limit setup before r0conf initialization

md/raid0: Move queue limit setup before r0conf initialization

Prepare for making logical blocksize configurable. This change has no
impact until logical block size becomes configurable.

Move raid0_set_limits() before create_strip_zones(). It is safe as fields
modified in create_strip_zones() do not involve mddev configuration, and
rdev modifications there are not used in raid0_set_limits().

'blksize' in create_strip_zones() fetches mddev's logical block size,
which is already the maximum aross all rdevs, so the later max() can be
removed.

Link: https://lore.kernel.org/linux-raid/20251103125757.1405796-4-linan666@huaweicloud.com
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Yu Kuai <yukuai@fnnas.com>