Cleanup temp files without rm

*** 47,56 ****
--- 47,57 ----
  
  $(__GNUC)LDLIBS +=      -lc
  $(__GNUC)LDFLAGS=       $(MAPFILE.NES:%=-Wl,-M%)
  
  $(ROOTONBLDMAN1ONBLDFILES) := FILEMODE=      644
+ CSTD=   $(CSTD_GNU99)
  
  # Assume we don't have the install.bin available yet
  INS.file=       $(RM) $@; $(CP) $< $(@D); $(CHMOD) $(FILEMODE) $@
  
  .KEEP_STATE: