Requested by nia@.
In unprivileged installations the binary becomes setuid to the
unprivileged user so it doesn't work even when ran as root via sudo,
due to privilege dropping upon execution.
XXX: Arguably this fix is wrong. It doesn't make sense to me that pkgsrc
infrastructure uses mode 4511 in SETUID_ROOT_PERMS when UNPRIVILEGED.
This package contains the intel_backlight program from intel-gpu-tools,
which allows controlling the backlight level on certain Intel(R) GPUs,
including i915.
Since it performs direct PCI access, it must be run as root.
