drm/sti: Fix return type of sti_{dvo,hda,hdmi}connectormode_valid()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.10.163 by commit 6e3c4d3fa5d458d685561ecbaf8daa9dba14979e. For more details please see the references link.