[NFC] Fix llvm-spirv LIT test location (#10810)

Looks like it got messed up in pulldown somehow here,
intel/llvm@22d83e0

It's currently in `test/` not `llvm-spirv/test/`, this moves it to
`llvm-spirv/test/` with the other tests.

Signed-off-by: Sarnie, Nick <[email protected]>

Author: sarnex