* libc/sys/linux/Makefile.am: Add support for new files.
* libc/sys/linux/Makefile.in: Regenerated.
* libc/sys/linux/ids.c: Add __getuid weak alias for getuid.
* libc/sys/linux/signal.c: Change to use real-time syscalls for
sigsuspend, sigprocmask, and sigpending. Also remove sigaction as
it is in a separate file now.
* libc/sys/linux/machine/i386/Makefile.am
* libc/sys/linux/machine/i386/Makefile.in
* libc/sys/linux/sys/signal.h: Add include of <bits/signum.h>.
* libc/sys/linux/sigaction.c: New file.
* libc/sys/linux/sigqueue.c: Ditto.
* libc/sys/linux/sigwait.c: Ditto.
* libc/sys/linux/machine/i386/sigaction.c: Ditto.
* libc/sys/linux/kernel_sigaction.h: Ditto.