octeontx2-af: modify FLR sequence for CPT

On OcteonTX2 platform CPT instruction enqueue is only
possible via LMTST operations.
The existing FLR sequence mentioned in HRM requires
a dummy LMTST to CPT but LMTST can't be submitted from
AF driver. So, HW team provided a new sequence to avoid
dummy LMTST. This patch adds code for the same.

Signed-off-by: Srujana Challa <schalla@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>