net: qualcomm: rmnet: Add support for ethtool private stats

Add ethtool private stats handler to debug the handling of packets
with checksum offload header / trailer. This allows to keep track of
the number of packets for which hardware computes the checksum and
counts and reasons where checksum computation was skipped in hardware
and was done in the network stack.

CRs-Fixed: 2226308
Change-Id: Ie0a28ec1e74ce7bbdd9271afd49f0f47d8df98a0
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-commit: bbde32d38bfbbc4a6970498c7470a8a817122735
Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git


Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>