fix SF bug 749486

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_4_BRANCH@20936 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

samples/mfc/makefile.b32

@@ -67,5 +67,9 @@ $(TARGET).res :      $(TARGET).rc
     brc32 -r /i$(BCCDIR)\include /i$(WXDIR)\include\msw /i$(WXDIR)\contrib\fafa $(TARGET)
 
 clean:
-        -erase *.obj *.exe *.res *.map *.rws
+        -$(RM) *.obj 
+        -$(RM) *.exe 
+        -$(RM) *.res 
+        -$(RM) *.map 
+        -$(RM) *.rws