commit bb6a7773 upstream.

We are seeing this warning: at net/core/skbuff.c:4174
and before commit a44878d1 ("IB/ipoib: Use one linear skb in RX flow")
skb truesize was not being set when ipoib was using just one skb.
Removing this line avoids the warning when running tcp tests like iperf.

Fixes: a44878d1 ("IB/ipoib: Use one linear skb in RX flow")
Signed-off-by: Carol L Soto <clsoto@linux.vnet.ibm.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>