net/mlx5: Devcom, serialize devcom registration

stable inclusion
from stable-v5.10.182
commit b556990235c33460a9d072b93f8dad3822ce4249
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8GJZJ

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b556990235c33460a9d072b93f8dad3822ce4249



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[ Upstream commit 1f893f57 ]

From one hand, mlx5 driver is allowing to probe PFs in parallel.
From the other hand, devcom, which is a share resource between PFs, is
registered without any lock. This might resulted in memory problems.

Hence, use the global mlx5_dev_list_lock in order to serialize devcom
registration.

Fixes: fadd59fc ("net/mlx5: Introduce inter-device communication mechanism")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>