btrfs: extent-tree: remove unused member walk_control::for_reloc

Leftover after fix e339a6b0 ("Btrfs: __btrfs_mod_ref should always
use no_quota"), that removed it from the function calls but not the
structure.
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/extent-tree.c

@@ -8330,7 +8330,6 @@ struct walk_control {
 	int keep_locks;
 	int reada_slot;
 	int reada_count;
-	int for_reloc;
 };
 
 #define DROP_REFERENCE	1
@@ -8967,7 +8966,6 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
 	wc->stage = DROP_REFERENCE;
 	wc->update_ref = update_ref;
 	wc->keep_locks = 0;
-	wc->for_reloc = for_reloc;
 	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
 
 	while (1) {
@@ -9133,7 +9131,6 @@ int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
 	wc->stage = DROP_REFERENCE;
 	wc->update_ref = 0;
 	wc->keep_locks = 1;
-	wc->for_reloc = 1;
 	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(fs_info);
 
 	while (1) {