'hwdev' is checked too late and hwdev will not be NULL, so remove the check

Fixes: 2acf960e ("net: hinic: Add support for configuration of rx-vlan-filter by ethtool")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202309112354.pikZCmyk-lkp@intel.com/Signed-off-by: Cai Huoqing <cai.huoqing@linux.dev>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>