xfs: refactor per-AG inode tagging functions

In preparation for adding another incore inode tree tag, refactor the
code that sets and clears tags from the per-AG inode tree and the tree
of per-AG structures, and remove the open-coded versions used by the
blockgc code.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
4 files changed