10075 make usr/src/tools smatch clean

*** 1,10 ****
--- 1,12 ----
  #
  # Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
  # Use is subject to license terms.
  #
  # Copyright 2011, Richard Lowe.
+ #
+ # Copyright (c) 2018, Joyent, Inc.
  
  include ../../Makefile.ctf
  
  LIBRARY=        libdwarf.a
  VERS=           .1
*** 75,84 ****
--- 77,89 ----
  
  CPPFLAGS +=     -I$(SRCDIR) -DELF_TARGET_ALL=1
  CERRWARN +=     -_gcc=-Wno-unused
  CERRWARN +=     -_gcc=-Wno-implicit-function-declaration
  
+ # libdwarf not clean
+ SMATCH=off
+ 
  LDLIBS = -lelf -lc
  
  .KEEP_STATE:
  .PARALLEL: