use RHOSTS in many places where we used RHOST

lib/msf/core/opt.rb

@@ -42,7 +42,7 @@ module Msf
 
     # @return [OptAddress]
     def self.RHOST(default=nil, required=true, desc="The target address")
-      Msf::OptAddress.new(__method__.to_s, [ required, desc, default ])
+      Msf::OptAddressRange.new('RHOSTS', [ required, desc, default ], aliases: [ 'RHOST' ])
     end
 
     # @return [OptPort]

lib/msf/ui/console/command_dispatcher/core.rb

@@ -1590,23 +1590,6 @@ class Core
       end
     end
 
-    # Warn when setting RHOST option for module which expects RHOSTS
-    if args.first.upcase.eql?('RHOST')
-      mod = active_module
-      unless mod.nil?
-        if !mod.options.include?('RHOST') && mod.options.include?('RHOSTS')
-          warn_rhost = false
-          if mod.exploit? && mod.datastore['PAYLOAD']
-            p = framework.payloads.create(mod.datastore['PAYLOAD'])
-            warn_rhost = (p && !p.options.include?('RHOST'))
-          else
-            warn_rhost = true
-          end
-          print_warning("RHOST is not a valid option for this module. Did you mean RHOSTS?") if warn_rhost
-        end
-      end
-    end
-
     # Set the supplied name to the supplied value
     name  = args[0]
     value = args[1, args.length-1].join(' ')