Merge branch 'ena-next'

Arthur Kiyanovski says:

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Improving performance and reducing latencies, by using latest capabilities exposed in ENA device

This patchset introduces the following:
1. A new placement policy of Tx headers and descriptors, which takes
advantage of an option to place headers + descriptors in device memory
space. This is sometimes referred to as LLQ - low latency queue.
The patch set defines the admin capability, maps the device memory as
write-combined, and adds a mode in transmit datapath to do header +
descriptor placement on the device.
2. Support for RX checksum offloading
3. Miscelaneous small improvements and code cleanups

Note: V1 of this patchset was created as if patches e2a322a 248ab77
from net were applied to net-next before applying the patchset. This V2
version does not assume this, and should be applyed directly on net-next
without the aformentioned patches.
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Signed-off-by: David S. Miller <davem@davemloft.net>