Set up a test suite that runs fluster in a virtual machine using virtme.
This test only runs when a kernel image path is set in the new
`virtme_kernel_image` meson option.

The kernel iimage must have support for visl.

The suite contains 4 tests, 1 for each supported codec in visl:
 - vp8
 - vp9
 - h.264
 - hevc

Part-of: <!5434>