xtensa.c: Include "df.h".

xtensa.c: Include "df.h".

	* config/xtensa/xtensa.c: Include "df.h".
	(xtensa_builtin_saveregs): Use adjust_address instead of change_address.
	(xtensa_va_start): Invoke make_tree with sizetype for
	expand_builtin_saveregs and then convert the result to a pointer.
	Use POINTER_PLUS_EXPR.  Use size_int instead of build_int_cst.
	(xtensa_gimplify_va_arg_expr): Use size_int instead of build_int_cst.
	Subtract argument size from index value as integers and then use
	POINTER_PLUS_EXPR to add the result to the array address.

From-SVN: r125854