octeontx2-af: Adjust LA pointer for cpt parse header

In case of ltype NPC_LT_LA_CPT_HDR, LA pointer is pointing to the
start of cpt parse header. Since cpt parse header has veriable
length padding, this will be a problem for DMAC extraction. Adding
KPU profile changes to adjust the LA pointer to start at ether header
in case of cpt parse header by
   - Adding ptr advance in pkind 58 to a fixed value 40
   - Adding variable length offset 7 and mask 7 (pad len in
     CPT_PARSE_HDR).
Also added the missing static declaration for npc_set_var_len_offset_pkind
function.

Signed-off-by: Kiran Kumar K <kirankumark@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>