Move rules_pkg_lib to //pkg

... next to the .bzl files. This is because the
//doc_build package is not loadable when rules_pkg itself
is not the root Bazel module, because stardoc is a
dev_dependency. So, //doc_build:rules_pkg_lib is not
usable by clients of rules_pkg.

Move the target to //pkg, next to the .bzl files.

Also add @rules_python//python:defs_bzl used by pkg_install.

Link: #897
Signed-off-by: HONG Yifan <[email protected]>

doc_build/BUILD

@@ -19,7 +19,6 @@ How to:
    git commit -m 'update docs' docs/latest.md
 """
 
-load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
 load("@rules_python//python:defs.bzl", "py_binary")
 load("@stardoc//stardoc:stardoc.bzl", "stardoc")
 load("//:version.bzl", "version")
@@ -111,14 +110,9 @@ stardoc(
     ],
 )
 
-# gather all rules that should be documented
-bzl_library(
+alias(
     name = "rules_pkg_lib",
-    srcs = [
-        "//:version.bzl",
-        "//pkg:bzl_srcs",
-        "@bazel_skylib//lib:paths",
-    ],
+    actual = "//pkg:rules_pkg_lib",
     visibility = ["//visibility:public"],
 )
 

pkg/BUILD

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
 load("@rules_pkg//pkg/private:make_starlark_library.bzl", "starlark_library")
 
 # -*- coding: utf-8 -*-
@@ -65,6 +66,18 @@ starlark_library(
     visibility = ["//visibility:public"],
 )
 
+# gather all rules that should be documented
+bzl_library(
+    name = "rules_pkg_lib",
+    srcs = [
+        "//:version.bzl",
+        "//pkg:bzl_srcs",
+        "@bazel_skylib//lib:paths",
+        "@rules_python//python:defs_bzl",
+    ],
+    visibility = ["//visibility:public"],
+)
+
 # Used by pkg_rpm in rpm.bzl.
 py_binary(
     name = "make_rpm",