Add qemu riscv64 testing support

Issue description

CIP currently supports qemu riscv64 for CIP 5.10 and 6.1 kernels, but we only currently only build in our CI. We need to add testing support as well.

Useful links

• CI pipelines are defined here
• CI scripts, image and test templates are defined here

Acceptance criteria

• Add support for boot testing for qemu riscv, using isar-cip-core

(LTP and other test cases will be added by other issues)