There are essentially two possible implementations for Setuid/Setgid on
Linux, either using SYS_SETUID32/SYS_SETGID32 or SYS_SETUID/SYS_SETGID,
depending on the architecture (see golang/go#1435 for why Setuid/Setgid
aren currently implemented for Linux neither in syscall nor in
golang.org/x/sys/unix).
Reduce duplication by merging the currently implemented variants and
adjusting the build tags accordingly.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Tobias Klauser