* init/paths.h (DEV_FD): Drop this definition, it's needless.
* init/job_process.c (job_process_run): Rather than using /dev/fd,
use /proc/self/fd which is more Linuxish and is always guaranteed to
exist when /proc is mounted - needing no symlinks.
* init/tests/test_job_process.c (test_run): Adjust test to match.