Fix build failure in `bazel test -s --config=opt --cache_test_results=no...

Fix build failure in `bazel test -s --config=opt --cache_test_results=no //tensorflow/python/kernel_tests:init_ops_test`

With the most recent master the following test fails:
```
bazel test -s --config=opt --cache_test_results=no //tensorflow/python/kernel_tests:init_ops_test
...
...
...
    eye = linalg_ops.eye(n, dtype=self.dtype)
NameError: global name 'linalg_ops' is not defined
```

This fix fixes the test failure.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>