Require Linux/ARM64 docker image for openebs/rawfile-localpv

[odidev]

Hi Team,  

I have been working on building openebs/rawfile-localpv images for both amd64 and arm64 platforms. I have modified the .travis.yaml to build and publish the docker images for arm64 platform.

Changes required: - odidev@682c05d

I have not added the e2e-testing for arm64 platform because e2e-testing requires minikube to run on travis for arm64 platform. And travisCI does not support minikube on arm64 platform. There is an open issue for this in kubernetes/minikube.

Do you have any plans for releasing arm64 images?  It will be very helpful if an arm64 image is available. If interested, I will raise a PR.

[odidev]

Hi Team,
A gentle reminder to take a look at the above changes.