IB/hfi1: checking for NULL instead of IS_ERR
IB/hfi1: checking for NULL instead of IS_ERR

__get_txreq() returns an ERR_PTR() but this checks for NULL so it would
oops on failure.

Signed-off-by: Dan Carpenter <ff341aa343d564f9e53e9dcb6996be8c04859a66@oracle.com>
Signed-off-by: Doug Ledford <f35204f44eabfe97bbcdd18aee9e9fffc59f29e1@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs