Use unless instead of if (not ...)

Author: averagesecurityguy

modules/auxiliary/scanner/mysql/mysql_writable_dirs.rb

@@ -45,7 +45,7 @@ def mysql_query_no_handle(sql)
   def run_host(ip)
     vprint_status("Login...")
 
-    if (not mysql_login_datastore)
+    unless mysql_login_datastore
       print_error('Unable to login to the server.')
       return
     end