DO NOT MERGE Fix potential DoS caused by delivering signal to BT process

Bug: 28885210
Change-Id: I63866d894bfca47464d6e42e3fb0357c4f94d360

 Conflicts:
	btif/co/bta_hh_co.c
	btif/src/btif_core.c
Merge conflict resolution of ag/1161415 (referencing ag/1164670)
- Directly into mnc-mr2-release

semaphore_t *semaphore_new(unsigned int value) {
 semaphore_t *ret = osi_malloc(sizeof(semaphore_t));
 if (ret) {
    ret->fd = eventfd(value, EFD_SEMAPHORE);
 if (ret->fd == INVALID_FD) {
      LOG_ERROR("%s unable to allocate semaphore: %s", __func__, strerror(errno));
      osi_free(ret);
      ret = NULL;
 }
 }
 return ret;
}

semaphore_t *semaphore_new(unsigned int value) {
 semaphore_t *ret = osi_malloc(sizeof(semaphore_t));
 if (ret) {
    ret->fd = eventfd(value, EFD_SEMAPHORE);
 if (ret->fd == INVALID_FD) {
      LOG_ERROR("%s unable to allocate semaphore: %s", __func__, strerror(errno));
      osi_free(ret);
      ret = NULL;
 }
 }
 return ret;
}
