All callers to xfs_dinode_good_version() and XFS_DINODE_SIZE() in
both the kernel and userspace have a xfs_mount structure available
which means they can use mount features checks instead looking
directly are the superblock.

Convert these functions to take a mount and use a xfs_has_v3inodes()
check and move it out of the libxfs/xfs_format.h file as it really
doesn't have anything to do with the definition of the on-disk
format.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>