meson: Fix install mode of Xorg SUID wrapper
Meson 0.47.0 is newer than our currently required version 0.46 by just several months, so we can start depending on it and fix install_mode for the Xorg SUID wrapper.
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Meson 0.47.0 is newer than our currently required version 0.46 by just several months, so we can start depending on it and fix install_mode for the Xorg SUID wrapper.