Warning patch

[Jeffrey A Law]

  In message < 199806050752.AAA04729@yorick.cygnus.com >you write:
  > Do all C compilers support cast to void?
  > 
  > 1998-06-05  Jason Merrill  <jason@yorick.cygnus.com>
  > 
  > 	* tree.h (TREE_VEC_END): Cast unused value to void.
  > 
  > 	* i386.c (print_operand): Use %lx for long operand.
I think we may already be using a cast to void elsewhere, so we're
probably OK.

The x86 change is fine too (I first thought we should be using
HOST_WIDE_INT_PRINT_HEX, but it turns out "long" really is the
right thing for that code.

jeff