vulkan: Support asymmetric FA in coopmat2 path (llama/21753)

vulkan: Support asymmetric FA in coopmat2 path (llama/21753)

* vulkan: Support asymmetric FA in coopmat2 path

There has been some recent interest/experimentation with mixed quantization
types for FA. I had originally designed the cm2 FA shader with this in mind
(because I didn't realize it wasn't supported at the time!), this change
adds the missing pieces and enables it.

Also support Q1_0 since people have been trying that out (seems crazy, but
who knows).

We should be able to do similar things in the coopmat1/scalar path, but
there's another change open against the scalar path and I don't want to
conflict.

* reorder cases