mlxsw: spectrum: Use correct PVID value when removing VLANs

When removing a range of VLANs in which PVID is a member we should use
the correct PVID value instead of some VLAN in the range.

Also, change two print statements to use 'dev' instead of
'mlxsw_sp_port->dev', as it's already used in other print statements in
the function.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>