RDMA/mlx5: Initialize phys_port_cnt earlier in RDMA device creation

RDMA/mlx5: Initialize phys_port_cnt earlier in RDMA device creation

phys_port_cnt of the IB device must be initialized before calling
ib_device_set_netdev().

Previously, phys_port_cnt was initialized in the mlx5_ib init function.
Remove this initialization to allow setting it separately, providing
the flexibility to call ib_device_set_netdev before registering the
IB device.

Signed-off-by: Chiara Meiohas <cmeiohas@nvidia.com>
Signed-off-by: Michael Guralnik <michaelgur@nvidia.com>
Link: https://patch.msgid.link/20240909173025.30422-4-michaelgur@nvidia.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>