RDMA/cxgb4: check for ipv6 address properly while destroying listener

RDMA/cxgb4: check for ipv6 address properly while destroying listener

ipv6 bit is wrongly set by the below which causes fatal adapter lookup
engine errors for ipv4 connections while destroying a listener.  Fix it to
properly check the local address for ipv6.

Fixes: 3408be145a5d ("RDMA/cxgb4: Fix adapter LE hash errors while destroying ipv6 listening server")
Link: https://lore.kernel.org/r/20210331135715.30072-1-bharat@chelsio.com
Signed-off-by: Potnuri Bharat Teja <bharat@chelsio.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>