libxfs: export unused nonstatic functions to quiet static checkers

libxfs: export unused nonstatic functions to quiet static checkers

libxfs functions which aren't used or exported get flagged as
"should be static" but we stay in sync with kernelspace, which has other
headers which export them.  Export the lot of them in libxfs_priv.h to
shut up sparse.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>