LU-8130 obd: remove limit on client mounts

LU-8130 obd: remove limit on client mounts

Using the in-kernel rhashtable instead of cfs_hash_table
for obd->obd_uuid_hash has a side effect of limiting number
of elements in the hash table and thereby limits max number
of Lustre clients by 16384.

The patch raises the limit to 2^31 (rhashtable default).

Fixes: e40b008e88 ("LU-8130 obd: convert obd uuid hash to rhashtable")
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: I222a6d0d2789ea9d1bb3530b3619d08ec83ebbe5
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/54186
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-by: Li Dongyang <dongyangli@ddn.com>