net/mlx5: Fix race between PCI error handlers and health work

Currently there is a race between the health care work and the kernel
pci error handlers because both of them detect the error, the first one
to be called will do the error handling.
There is a chance that health care will disable the pci after resuming
pci slot.
Also create a separate WQ because now we will have two types of health
works, one for the error detection and one for the recovery.

Fixes: 89d44f0a ('net/mlx5_core: Add pci error handlers to mlx5_core driver')
Signed-off-by: Mohamad Haj Yahia <mohamad@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>