futex: move fallback definitions of futex constants to xlat/

futex: move fallback definitions of futex constants to xlat/

* futex.c: Move definitions of FUTEX_OP_CMP_* constants ...
* xlat/futexwakecmps.in: ... here.
* futex.c: Move definitions of other FUTEX_OP_* constants ...
* xlat/futexwakeops.in: ... here.
* futex.c: Move definitions of remaining FUTEX_* constants except
FUTEX_PRIVATE_FLAG and FUTEX_CLOCK_REALTIME flags ...
* xlat/futexops.in: ... here.