Fix pylint issue in the master branch

Fix pylint issue in the master branch

The latest master branch has the following pylint failure that caused
`Ubuntu Sanity — Internal CI build failed`:
```
53 FAIL: Found 2 non-whitelited pylint errors:
54 tensorflow/contrib/cmake/tools/create_def_file.py:47: [C0301(line-too-long), ] Line too long (106/80)
55
56 tensorflow/contrib/cmake/tools/create_def_file.py:61: [C0301(line-too-long), ] Line too long (90/80)
```

This PR addresses the above issues.

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