tools: do not check starpu_perfmodel_display and starpu_perfmodel_plot on a windows machine

tools/Makefile.am

@@ -92,9 +92,12 @@ STARPU_TOOLS	+=			\
 endif
 
 STARPU_TOOLS	+=			\
+	starpu_machine_display
+
+if !STARPU_HAVE_WINDOWS
+STARPU_TOOLS	+=			\
 	starpu_perfmodel_display	\
 	starpu_perfmodel_plot 		\
-	starpu_machine_display
 
 noinst_PROGRAMS =	cbc2paje lp2paje