Summary:
This is necessary to keep openQA working, which uses LLVMpipe as a
renderer on a Cirrus device that operates in depth 16.
LLVMpipe advertises 24/32 bit sRGB configurations on this setup, but
they cannot be presented.
CCBUG: 408594
Test Plan: Compile tested only.
Reviewers: fvogt, #kwin, zzag
Reviewed By: fvogt, #kwin, zzag
Subscribers: romangg, sbergeron, fvogt, kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D22203
4982dfd5f5