octeontx2-af: Sync NIX and NPA contexts from NDC to LLC/DRAM

Octeontx2 hardware uses Near Data Cache(NDC) block to cache
contexts in it so that access to LLC/DRAM can be avoided.
It is recommended in HRM to sync the NDC contents before
releasing/resetting LF resources. Hence implement NDC_SYNC
mailbox and sync contexts during driver teardown.

Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>