pmf_init reported stream dimensions without a cap, and PMFView::Draw
allocated width * height * 4 with 32-bit int arithmetic, so a crafted
ICON1.PMF could overflow the allocation to a small buffer while
sws_scale wrote the full frame.
- Reject videos with dimensions outside 1..720x480 in pmf_init (PMFs on
the PSP never exceed 720x480).
- Use size_t arithmetic for the frame buffer allocation.
Henrik Rydgård
5d10f281ef