btrfs: move __TRANS_* and TRANS_* flags out of transaction.h

Among all those flags, only __TRANS_DUMMY is used outside of
transaction.[ch], and there are only two places using it:

- find_parent_nodes()
  Introduce a helper, btrfs_trans_is_dummy(), for this call site.

- btrfs_init_dummy_trans()
  Move the function into transaction.[ch], and hide it behind
  CONFIG_BTRFS_FS_RUN_SANITY_TESTS.

With the above changes, we can hide __TRANS_* and TRANS_* flags inside
transaction.c. This allows us to modify those flags in the future
without causing any changes to existing callers.

After the flags relocation, now we can also hide __TRANS_DUMMY behind
CONFIG_BTRFS_FS_RUN_SANITY_TESTS.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

0 files changed, 0 insertions, 0 deletions