* libc/include/sys/features.h: Define _POSIX_TIMERS for spu.
* libc/include/sys/unistd.h: Change usleep prototype to Posix
form and move outside of OS flag checks.
* libc/machine/spu/Makefile.am: Add sleep and usleep.
* libc/machine/spu/Makefile.in: Regenerate.
* libc/machine/spu/sleep.c: Copy libc/posix/sleep.c.
* libc/machine/spu/usleep.c: Copy libc/posix/usleep.c.
Jeff Johnston