acos.s fix: use the formula acos(x) = atan2(sqrt(1-x),sqrt(1+x))

[musl] / src / linux / adjtimex.c

#include <sys/timex.h>
#include "syscall.h"

int adjtimex(struct timex *tx)
{
        return syscall(SYS_adjtimex, tx);
}