IB/mlx4: Remove limitation on LSO header size

Current code has a limitation: an LSO header is not allowed to cross a
64 byte boundary.  This patch removes this limitation by setting the
WQE RR for large headers thus allowing LSO headers of any size.  The
extra buffer reserved for MLX4_IB_QP_LSO QPs has been doubled, from 64
to 128 bytes, assuming this is reasonable upper limit for header
length.  Also, this patch will cause IB_DEVICE_UD_TSO to be set only
for HCA FW versions that set MLX4_DEV_CAP_FLAG_BLH; e.g. FW version
2.6.000 and higher.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/net/mlx4/fw.c

@@ -90,6 +90,7 @@ static void dump_dev_cap_flags(struct mlx4_dev *dev, u32 flags)
 		[ 9] = "Q_Key violation counter",
 		[10] = "VMM",
 		[12] = "DPDP",
+		[15] = "Big LSO headers",
 		[16] = "MW support",
 		[17] = "APM support",
 		[18] = "Atomic ops support",