Merge branch 'rmnet-Configuration-options'

Subash Abhinov Kasiviswanathan says:

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net: qualcomm: rmnet: Configuration options

This series adds support for configuring features on rmnet devices.
The rmnet specific features to be configured here are aggregation and
control commands.

Patch 1 is a cleanup of return codes in the transmit path.
Patch 2 removes some redundant ingress and egress macros.
Patch 3 restricts the creation of rmnet dev to one dev per mux id for a
given real dev.
Patch 4 adds ethernet data path support.
Patches 5-6 add support for configuring features on new and existing
rmnet devices.

v1->v2:
The memory leak fixed as part of patch 1 is merged seperately as
a896d94abd2c ("net: qualcomm: rmnet: Fix leak on transmit failure").
Fix a use after free in patch 4 if a packet with headroom lesser than ethernet
header length is received.

v2->v3:
Fix formatting problem in patch 5 in the return statement.
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Signed-off-by: David S. Miller <davem@davemloft.net>