Remove `import` use from TARGETS

Summary:
We're moving away from `import`. The equivalent internal construct that
gets the directory from `fbcode/` is `package_name()`. This is a
Skylark friendly wrapper around [`get_base_path`].

The additional whitespace change is from running `python ./buckifier/buckify_rocksdb.py`.

[`get_base_path`]: https://buckbuild.com/function/get_base_path.html
Closes https://github.com/facebook/rocksdb/pull/3210

Reviewed By: yiwu-arbug

Differential Revision: D6451242

Pulled By: zertosh

fbshipit-source-id: 445757261de0ec89d5d332c1ba9af097086326dc

TARGETS

-import os
-
-TARGETS_PATH = os.path.dirname(__file__)
-
-REPO_PATH = TARGETS_PATH[(TARGETS_PATH.find('fbcode/') + len('fbcode/')):] + "/"
+REPO_PATH = package_name() + "/"
 
 BUCK_BINS = "buck-out/gen/" + REPO_PATH
 

buckifier/targets_cfg.py

@@ -2,11 +2,7 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 from __future__ import unicode_literals
-rocksdb_target_header = """import os
-
-TARGETS_PATH = os.path.dirname(__file__)
-
-REPO_PATH = TARGETS_PATH[(TARGETS_PATH.find('fbcode/') + len('fbcode/')):] + "/"
+rocksdb_target_header = """REPO_PATH = package_name() + "/"
 
 BUCK_BINS = "buck-out/gen/" + REPO_PATH