tape: change code hierarchy to improve docs

src/bin/proxmox_tape/changer.rs

@@ -19,8 +19,10 @@ use proxmox_backup::{
         },
     },
     tape::{
-        complete_changer_path,
-        media_changer,
+        drive::{
+            media_changer,
+            complete_changer_path,
+        },
     },
     config::{
         self,

src/bin/proxmox_tape/drive.rs

@@ -17,9 +17,7 @@ use proxmox_backup::{
             DRIVE_NAME_SCHEMA,
         },
     },
-    tape::{
-        complete_drive_path,
-    },
+    tape::drive::complete_drive_path,
     config::drive::{
         complete_drive_name,
         complete_changer_name,