10080 smatch Makefile changes for usr/src/cmd

*** 107,116 ****
--- 107,118 ----
  CERRWARN += -_gcc=-Wno-clobbered
  CERRWARN += -_gcc=-Wno-parentheses
  CERRWARN += -_gcc=-Wno-unused-label
  CERRWARN += -_gcc=-Wno-unused-variable
  
+ SMOFF += all_func_returns
+ 
  #
  # -erroff=E_INCONS_ARG_DECL2 works around a problem where lint gets confused
  # about how struct mdb_tgt_gregset is used in mdb_tgt_stack_f() and
  # mdb_tgt_stack_iter_f(). Will be resolved as part of fix for CR 6749868.
  #