Remove NGLAYOUT_PLUGINS useless define.

modules/plugin/makefile.win

@@ -20,11 +20,9 @@ DEPTH=..\..
 #// DIRS          - There are subdirectories to process
 #//
 #//------------------------------------------------------------------------
-!if !defined(NGLAYOUT_PLUGINS)
+
-DIRS= public src
-!else
 DIRS= public nglsrc
-!endif
+
 #//------------------------------------------------------------------------
 #//
 #// Include the common makefile rules