The Rangers forward replaces Aberdeen striker Josh Magennis, who has withdrawn due to a knee injury.
Little, who made his Northern Ireland debut in 2009, said he was
"delighted" to be back in the squad.
O'Neill's men take on Azerbaijan on Friday and Israel four days later.
Aaron Hughes misses
the qualifiers because of a groin injury, with
Bradford City's Rory McArdle coming in as his replacement.
Chris Brunt, Chris Baird and Sammy
Clingan return, however there is no place for Barnsley and ex-Celtic winger Paddy McCourt.