treewide: introduce osbase package and move things around

All except localregistry moved from metropolis/pkg to osbase,
localregistry moved to metropolis/test as its only used there anyway.

Change-Id: If1a4bf377364bef0ac23169e1b90379c71b06d72
Reviewed-on: https://review.monogon.dev/c/monogon/+/3079
Tested-by: Jenkins CI
Reviewed-by: Serge Bazanski <serge@monogon.tech>
diff --git a/metropolis/node/build/mkimage/main.go b/metropolis/node/build/mkimage/main.go
index 7de951e..3695054 100644
--- a/metropolis/node/build/mkimage/main.go
+++ b/metropolis/node/build/mkimage/main.go
@@ -34,8 +34,8 @@
 	"os"
 
 	"source.monogon.dev/metropolis/node/build/mkimage/osimage"
-	"source.monogon.dev/metropolis/pkg/blkio"
-	"source.monogon.dev/metropolis/pkg/blockdev"
+	"source.monogon.dev/osbase/blkio"
+	"source.monogon.dev/osbase/blockdev"
 )
 
 //go:embed metropolis/node/core/abloader/abloader_bin.efi