create get_implied_range_list()

create get_implied_range_list()

The original code in smatch_extra handled assignments by
basically saying:
	set_state_expr(my_id, left, get_implied_value(right));

The problem is that if right was a range instead of value it
defaulted to undefined.  The new code handles this correctly.

The other thing is the new code handles "a = x % FOO;"

Signed-off-by: Dan Carpenter <error27@gmail.com>