pos_stock_quantity/views/config.xml

<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
        <record id="pos_config" model="ir.ui.view">
            <field name="name">pos.config</field>
            <field name="model">pos.config</field>
            <field name="inherit_id" ref="point_of_sale.view_pos_config_form"/>
            <field name="arch" type="xml">
                <xpath expr='//sheet/group[1]' position='after'>
                    <group string="POS Stock">
                        <group>
                            <field name="show_qty_available"/>
                        </group>
                        <group
                               attrs="{'invisible':[('show_qty_available','=',False)]}">
                            <field name="location_only"/>
                            <field name="hide_product" attrs="{'invisible':[
                        ('location_only','=',False)]}"/>
                        </group>
                        <group attrs="{'invisible':[('show_qty_available','=',False)]}">
                            <field name="allow_out_of_stock"/>
                            <field name="limit_qty" attrs="{'invisible':[('allow_out_of_stock','=',True)]}"
                                   style="width: 150px;"/>
                        </group>
                    </group>
                </xpath>
            </field>
        </record>
    </data>
</openerp>