[mlir][XeVM] Use libocloc API for binary generation. (#188353)
This PR improves native binary generation by avoiding
`llvm::sys::ExecuteAndWait` call for ocloc and instead
leveraging `oclocInvoke()` that consumes an in-memory SPIR-V string.
Co-authored-by: Artem Kroviakov <artem.kroviakov@intel.com>