detect rng seed strength at runtime based on algorithm not compile time based on platform features

sys/unix/unixmain.c

@@ -776,6 +776,7 @@ sys_random_seed()
     fptr = fopen(DEV_RANDOM, "r");
     if (fptr) {
         fread(&seed, sizeof(long), 1, fptr);
+        has_strong_rngseed = TRUE;
     }
     fclose(fptr);
 #else