net/ibmvnic: Remove tests of member address

The driver was checking for non-NULL address.
- adapter->napi[i]

This is pointless as these will be always non-NULL, since the
'dapter->napi' is allocated in init_napi().
It is safe to get rid of useless checks for addresses to fix the
coccinelle warning:
>>drivers/net/ethernet/ibm/ibmvnic.c: test of a variable/field address
Since such statements always return true, they are redundant.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Michael Ellerman <mpe@ellerman.id.au>
CC: Thomas Falcon <tlfalcon@linux.ibm.com>
CC: John Allen <jallen@linux.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: linuxppc-dev@lists.ozlabs.org
CC: netdev@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>