The guest video out had no way to tell a title that the display it presents
is smaller than the one the title assumes: the buffer attribute the title
writes was taken as it was, so a title that renders 3840x2160 and presents it
in a 1920x1080 window pays for the 4K render and shows it letterboxed.
ANYPS5_VIDEO_OUT_MAX_WIDTH and ANYPS5_VIDEO_OUT_MAX_HEIGHT clamp every buffer
attribute the guest registers, through the set-attribute helpers or directly
through sceVideoOutRegisterBuffers2 or sceVideoOutRegisterBuffers, and answer
an output mode the host does not implement as unsupported when either limit
is set, so the title registers a buffer the host can show and renders at that
size. sceVideoOutConfigureOutput now treats that unsupported answer as
VIDEO_OUT_ERROR_UNSUPPORTED_OUTPUT_MODE instead of proceeding to configure
the mode. Each limit is a positive decimal integer; an unset, empty, malformed
or zero value disables that axis. The two axes clamp independently, so a
buffer whose aspect ratio is not 16:9 can change its presented aspect ratio.
