Fix startup crash when libcrypto symbols are missing

doc/UPDATES

@@ -5,6 +5,7 @@ maint
   * Fix help for 'topic' to show optional channel argument
   * Fix cmd_hublevel not properly requiring a hublevel argument
   * Fix build with clang (FreeBSD 10)
+  * Fix startup crash when some libcrypto symbols were missing
 
 1.4.3
   * Default 'set promisc' to ignore since it's usually a false positive

src/libcrypto.c

@@ -111,7 +111,10 @@ int load_libcrypto() {
     return(1);
   }
 
-  load_symbols(libcrypto_handle);
+  if (load_symbols(libcrypto_handle)) {
+    fprintf(stderr, STR("Missing symbols for libcrypto (likely too old)\n"));
+    return(1);
+  }
 
   return 0;
 }