Land #10790, don't log peer if it represents > 1 target

lib/msf/core/exploit/tcp.rb

@@ -196,8 +196,12 @@ module Exploit::Remote::Tcp
   end
 
   def print_prefix
-    if rhost
-      super + peer + " - "
+    # Only inject a host/port prefix if we have exactly one entry.
+    # Otherwise we are logging in the global context where rhost can be any
+    # size (being an alias for rhosts), which is not very useful to insert into
+    # a single log line.
+    if rhost && rhost.split(' ').length == 1
+      super + peer + ' - '
     else
       super
     end