octeontx2-af: Add NIX RQ, SQ and CQ contexts to debugfs

To aid in debugging NIX block related issues, added support to dump
NIX block LF's RQ, SQ and CQ hardware contexts in debugfs. User can
check which contexts are enabled currently and dump it's current HW
context.

Four new files 'qsize', 'rq_ctx', 'sq_ctx' and 'cq_ctx' are added to the
debugfs at 'sys/kernel/debug/octeontx2/nix/'

'echo <nixlf index> > qsize' will display current enabled CQ/SQ/RQs.
'echo <nixlf> [rq number/all] > rq_ctx',
'echo <nixlf> [sq number/all] > sq_ctx' &
'echo <nixlf> [cq number/all] > cq_ctx' will dump RQ/SQ/CQ's current
hardware context.

Signed-off-by: Prakash Brahmajyosyula <bprakash@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>