[truetype] Fix CVAR handling of tuples for all points.

* src/truetype/ttgxvar (tt_face_vary_cvt): Function
`ft_var_readpackedpoints`, when it returns `ALL_POINTS`, also sets
`point_count` to value 0.  However, the CVAR code was incorrectly expecting
that `point_count` would be set to match the length of the CVT table.
1 file changed