Non ANSI C declaration of block local variable in NetworkInterface_winXP.c

Change "8168405: Pending exceptions in java.base/windows/native" introduced the following non ANSI C compatible code for declaring a block-level variable ("jboolean ret"):

        } else /* AF_INET6 */ {
            int scope;
            iaObj = (*env)->NewObject(env, ia6_class, ia6_ctrID);
            if (iaObj == NULL) {
                return NULL;
            }
            jboolean ret = setInet6Address_ipaddress(env, iaObj, (jbyte *)&(addrs->addr.sa6.sin6_addr.s6_addr));

But ANSI C only allows the declaration of block local variable at the beginning of a block.Unfortunately some still very common compiler like VS2010 and VS2012 still don't support this C99 feature :(