mlxsw: spectrum: Remove redundant errors from the code

Currently, when device configuration fails we emit errors to the kernel
log despite the fact we already get these from the EMAD transaction
layer, so remove them.

In addition to being unnecessary, removing these error messages will
allow us to reuse mlxsw_sp_port_add_vid() to create the PVID vPort
before registering the netdevice.

Fixes: 99724c18

 ("mlxsw: spectrum: Introduce support for router interfaces")
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>