Merge branch 'korina-performance-fixes-and-cleanup'

Roman Yeryomin says:

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korina: performance fixes and cleanup

Changes from v1:
- use GRO instead of increasing ring size
- use NAPI_POLL_WEIGHT instead of defining own NAPI_WEIGHT
- optimize rx descriptor flags processing
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Signed-off-by: David S. Miller <[email protected]>