Some VNC cleanups
Inspired by !979 (merged), which includes similar changes in the RDP backend:
Use xzalloc() instead of manual OOM handling, set static properties during head creation, fix mode flags, and drop unnecessary output release.
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Inspired by !979 (merged), which includes similar changes in the RDP backend:
Use xzalloc() instead of manual OOM handling, set static properties during head creation, fix mode flags, and drop unnecessary output release.