rust: better panic message for missing file config

(cherry picked from commit aee8e60149)

rust/src/http2/http2.rs

@@ -785,7 +785,7 @@ impl HTTP2State {
                                     );
                                 }
                             }
-                            None => panic!("BUG"),
+                            None => panic!("no SURICATA_HTTP2_FILE_CONFIG"),
                         }
                     }
                     input = &rem[hlsafe..];

rust/src/nfs/nfs.rs

@@ -300,7 +300,7 @@ pub fn filetracker_newchunk(ft: &mut FileTransferTracker, files: &mut FileContai
         Some(sfcm) => {
             ft.new_chunk(sfcm, files, flags, &name, data, chunk_offset,
                     chunk_size, fill_bytes, is_last, xid); }
-        None => panic!("BUG"),
+        None => panic!("no SURICATA_NFS_FILE_CONFIG"),
     }
 }
 

rust/src/smb/files.rs

@@ -89,7 +89,7 @@ pub fn filetracker_newchunk(ft: &mut FileTransferTracker, files: &mut FileContai
         Some(sfcm) => {
             ft.new_chunk(sfcm, files, flags, &name, data, chunk_offset,
                     chunk_size, fill_bytes, is_last, xid); }
-        None => panic!("BUG"),
+        None => panic!("no SURICATA_SMB_FILE_CONFIG"),
     }
 }