LU-16894 lod: fix stripe_count limit in lod_qos_set_pool

LU-16894 lod: fix stripe_count limit in lod_qos_set_pool

For a conflicting pool name and stripe offset parameter, the MDS
should not set the pool on the file layout in favor of the stripe
offset (LU-15658). But lod_qos_set_pool() still limit the
stripe_count to the number of OSTs in the specified pool.

Let's fix this.

Fixes: 06dd5a4 ("LU-15658 lod: ost list and pool name conflict")
Signed-off-by: Etienne AUJAMES <eaujames@ddn.com>
Change-Id: Ic47f9aadd8feea01367e526aaf0ea41a69ade9fa
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/51314
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Alexander Boyko <alexander.boyko@hpe.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>