linux-dmabuf: fix bound checks for stride and height
linux-dmabuf: fix bound checks for stride and height

- Fix bound checking for offset + stride * height
- Make offset bound checking more consistent
- Reject zero strides

ascent12/wlroots,SirCmpwn/wlroots,ascent12/wlroots,swaywm/wlroots,swaywm/wlroots