10080 smatch Makefile changes for usr/src/cmd

*** 21,30 ****
--- 21,31 ----
  #
  #
  # Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
  # Use is subject to license terms.
  #
+ # Copyright (c) 2018, Joyent, Inc.
  
  include ../../Makefile.cmd
  
  LIBADMDIR = ../../../lib/libadm/inc
  CPPFLAGS += -I$(LIBADMDIR)
*** 36,45 ****
--- 37,48 ----
  LDLIBS += -ladm
  
  CERRWARN += -_gcc=-Wno-parentheses
  CERRWARN += -_gcc=-Wno-uninitialized
  
+ SMOFF += signed
+ 
  .KEEP_STATE:
  
  .PARALLEL: $(PROG)
  
  all: $(PROG)