Fix Arm issue for rancher

[niusmallnan]

We tested Rancher on the Arm server (HUAWEI) of a Chinese customer and found that there was a problem with our rke-tools and its built-in confd could not run. However, this problem cannot be reproduced on the AWS Arm instance.

We need to release a new version of confd and make a PR to rke-tools to address this issue.

[niusmallnan]

ping @cjellick

[290760647]

We are about to sign a contract with a customer GEOVIS/Kongtian Institute. The server chips they use are Huawei arm processor Kunpeng and PHYTIUM FT-2000, but currently confd components cannot be used normally in these two environments. Hope to support it as soon as possible

[kinarashah]

Thanks for the PR @niusmallnan! Pulled in related arm changes, switch to go modules and fixing our build stuff in this PR together #3.

Can be tested with confd v0.16.2, rke-tools v0.1.69 for k8s versions in Rancher v2.4.13-rc3 mentioned here.

[XeonForce]

confd v0.16.2 cannot run on my Huawei Kunpeng arm server.

I tried to build from source and it works fine.

# go 1.16 | Windows10
SET CGO_ENABLED=0
SET GOOS=linux
SET GOARCH=arm64
go build

It seems that there is a problem with the officially released version.
I found that the file of arm and arm64 is the same. It should be caused by mistakenly building arm64 as arm.

# sha256sum.txt
e08a185763f1fd8a15e55937553669af72ab7dcc8eb3117704551032e5eae6e6  bin/confd-v0.16.2-linux-arm
e08a185763f1fd8a15e55937553669af72ab7dcc8eb3117704551032e5eae6e6  bin/confd-v0.16.2-linux-arm64

Hope to fix it asap.