Fix cross-compiling unclosed CMake variable (did not trigger in presubmit).
Fix cross-compiling unclosed CMake variable (did not trigger in presubmit).

iree-org/iree,google/iree,google/iree,iree-org/iree,google/iree,iree-org/iree,google/iree,iree-org/iree,iree-org/iree,google/iree,google/iree,google/iree,iree-org/iree,iree-org/iree