add export_file to rockdb TARGETS generator and re-gen

Summary:
we are converting the implicit loads to explicit loads, then remove the hidden loads in fbcode macroes.
details see https://fb.workplace.com/groups/devx.build.bffs/permalink/7481848805183560/

Reviewed By: JakobDegen

Differential Revision: D57800976

fbshipit-source-id: a893aa2aa9237704ba9eb998cba210222c95dd2f

Author: Fan Zhang(DevX)

TARGETS

@@ -4,6 +4,7 @@
 # This file is a Facebook-specific integration for buck builds, so can
 # only be validated by Facebook employees.
 load("//rocks/buckifier:defs.bzl", "cpp_library_wrapper","rocks_cpp_library_wrapper","cpp_binary_wrapper","cpp_unittest_wrapper","fancy_bench_wrapper","add_c_test_wrapper")
+load("@fbcode_macros//build_defs:export_files.bzl", "export_file")
 
 
 cpp_library_wrapper(name="rocksdb_lib", srcs=[

buckifier/targets_cfg.py

@@ -7,6 +7,7 @@
 # This file is a Facebook-specific integration for buck builds, so can
 # only be validated by Facebook employees.
 load("//rocks/buckifier:defs.bzl", "cpp_library_wrapper","rocks_cpp_library_wrapper","cpp_binary_wrapper","cpp_unittest_wrapper","fancy_bench_wrapper","add_c_test_wrapper")
+load("@fbcode_macros//build_defs:export_files.bzl", "export_file")
 
 """
 

unreleased_history/bug_fixes/buck_explicit_load.md

@@ -0,0 +1 @@
+* [internal only] Build script improvement