[core] attempt to quiet compiler warning in LEDE
@@ -113,7 +113,8 @@ static int li_rand_device_bytes (unsigned char *buf, int num)
ssize_t rd = 0;
#ifdef RNDGETENTCNT
int entropy;
- if (0 == ioctl(fd, RNDGETENTCNT, &entropy) && entropy >= num*8)
+ if (0 == ioctl(fd, (unsigned long)(RNDGETENTCNT), &entropy)
+ && entropy >= num*8)
#endif
rd = read(fd, buf, (size_t)num);
close(fd);
