[SRU][linux-aws] update ENA driver to latest mainline version 1.5.0K

[Kamal Mostafa]

BugLink: http://bugs.launchpad.net/bugs/1774490
update ENA driver to latest mainline version 1.5.0K

The following pull requests for linux-aws-xenial and linux-aws-bionic
update Amazon ENA ethernet driver to the latest mainline version.
These are all clean cherry-picks from mainline.

[Impact]

A couple of rare ENA bugs fixed; no expected change to normal functionality
or performance.

[Test Case]

Smoke tests of ENA-enabled instances show no discrepant behavior.

[Regression Potential]

Minimal: changes restricted to the ENA driver.

Thanks,

 -Kamal