libsparse: move_chunks_up_to_len() does not account skip chunks

I caught the fastboot host command sending more data than the fastboot
device can accept.  Fastboot host command was sending 36 surplus bytes
because of 3 skip chunks that were not taken into account in
move_chunks_up_to_len() algorithm.

Change-Id: I39a4a033c9b15893bd70e553f17116735ee4a48e