remove api_schema submodule

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

src/bin/dump-backup-api.rs

@@ -1,7 +1,8 @@
 use failure::*;
 
+use proxmox::api::format::*;
+
 use proxmox_backup::api2;
-use proxmox_backup::api_schema::format::*;
 
 fn main() -> Result<(), Error> {
 

src/bin/dump-reader-api.rs

@@ -1,7 +1,8 @@
 use failure::*;
 
+use proxmox::api::format::dump_api;
+
 use proxmox_backup::api2;
-use proxmox_backup::api_schema::format::*;
 
 fn main() -> Result<(), Error> {