clarify debug-level log while initializing entropy

I got confused when I saw my Tor saying it was opening a file
that doesn't exist. It turns out it isn't opening it, it's just
calling open() on it and then moving on when it's not there.

src/common/crypto.c

@@ -2895,7 +2895,7 @@ crypto_strongest_rand_fallback(uint8_t *out, size_t out_len)
   size_t n;
 
   for (i = 0; filenames[i]; ++i) {
-    log_debug(LD_FS, "Opening %s for entropy", filenames[i]);
+    log_debug(LD_FS, "Considering %s for entropy", filenames[i]);
     fd = open(sandbox_intern_string(filenames[i]), O_RDONLY, 0);
     if (fd<0) continue;
     log_info(LD_CRYPTO, "Reading entropy from \"%s\"", filenames[i]);