xfs: move various type verifiers to common file

New verification functions like xfs_verify_fsbno() and
xfs_verify_agino() are spread across multiple files and different
header files. They really don't fit cleanly into the places they've
been put, and have wider scope than the current header includes.

Move the type verifiers to a new file in libxfs (xfs-types.c) and
the prototypes to xfs_types.h where they will be visible to all the
code that uses the types.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>