Q2A SSO use WP user and WordPress by default doesn't allows to upload user avatar but your user can use gravatar and if they have already it will automatically appear.
If you want to allow your user to change avatar than you may need to install plugin in WordPress with allows your user to upload avatar.
some of are here
http://wordpress.org/plugins/wordpress-custom-avatars-plugin/
http://wordpress.org/plugins/simple-local-avatars/
http://wordpress.org/plugins/proper-avatars/
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