use umount2 syscall for umount (new targets lack old 1-arg umount)

[musl] / src / thread / pthread_rwlock_init.c

#include "pthread_impl.h"

int pthread_rwlock_init(pthread_rwlock_t *rw, const pthread_rwlockattr_t *a)
{
        memset(rw, 0, sizeof *rw);
        if (a) {
        }
        return 0;
}