Build failure with riscv32

In file included from thread/qmutex_linux.cpp:45,
 from thread/qmutex.cpp:804:
thread/qfutex_p.h: In function 'int QtLinuxFutex::_q_futex(int*, int, int, quintptr, int*, int)':
thread/qfutex_p.h:116:30: error: '__NR_futex' was not declared in this scope; did you mean '_q_futex'?
 116 | int result = syscall(__NR_futex, addr, op | FUTEX_PRIVATE_FLAG, val, val2, addr2, val3);
 | ^~~~~~~~~~
 | _q_futex