m/node/allocs: split new package off m/node

The metropolis/node package contains various unrelated things. One of
these things are node-wide allocations of identifiers.
These are moved here to the new metropolis/node/allocs package.
Additionally, the constants are renamed to move the type of identifier
in front.

Change-Id: Ibc841ca64d4450a7054463e6d2d44753a118e07a
Reviewed-on: https://review.monogon.dev/c/monogon/+/4566
Reviewed-by: Tim Windelschmidt <tim@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/node/BUILD.bazel b/metropolis/node/BUILD.bazel
index 6168e48..e69d00a 100644
--- a/metropolis/node/BUILD.bazel
+++ b/metropolis/node/BUILD.bazel
@@ -9,19 +9,12 @@
 go_library(
     name = "node",
     srcs = [
-        "ids.go",
         "labels.go",
-        "net_ips.go",
-        "net_protocols.go",
         "net_status.go",
-        "ports.go",
         "validation.go",
     ],
     importpath = "source.monogon.dev/metropolis/node",
-    visibility = [
-        "//metropolis:__subpackages__",
-        "@io_k8s_kubernetes//pkg/registry:__subpackages__",
-    ],
+    visibility = ["//metropolis:__subpackages__"],
     deps = ["//metropolis/proto/common"],
 )