arm: add __aeabi_atexit()

[musl] / arch / arm / src / __aeabi_atexit.c

int __cxa_atexit(void (*func)(void *), void *arg, void *dso);

int __aeabi_atexit (void *obj, void (*func) (void *), void *d)
{
        return __cxa_atexit (func, obj, d);
}