Add support for s390x architecture

[dilipgb]

Describe the Enhancement

Please extend support for jam cli to s390x architecture. This is required to build s390x based packeto-community stacks for s390x (multiarch stacks).

Motivation

Buildpacks are default builder in knative functions. s390x adopted to use knative functions using s2i builder and we are looking to extend our support to s390x architecture. This provides users the capabilities to choose the builder of there choice to build there apps using knative functions.

[dilipgb]

Hi, I'm drafting the PR for the same issue. Please take a look at this. #337