LU-16157 lnet: lst read-outside of allocation

LU-16157 lnet: lst read-outside of allocation

lnet_selftest want a some parameters from userspace,
but it never sends. It caused a read of outside of allocation
like
BUG: KASAN: slab-out-of-bounds in lstcon_testrpc_prep+0x19e7/0x1bb0
Read of size 4 at addr ffff8888bbaa866c by task lt-lst/6371

Signed-off-by: Alexey Lyashkov <alexey.lyashkov@hpe.com>
Change-Id: I2a98e60c4be65c49fa9da4b418e50f1c7309b69d
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/48547
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>