skia: update interfaces to libpng 1.5.7 beta 01

Libpng 1.5.7 beta 01 is integrated, where some interfaces are
changed and some structures are not visible to libpng clients
any more. The structure information can be retrieved through
specific interfaces.

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
1 file changed