Coverity defect: Resource leak 13110
    
    This commit 94b123780b21e503b78bceca9d60904206ef91fa
    introduced the resource leak.
    Trac Ticket #447 - Possible to add invalid attribute
        to nsslapd-allowed-to-delete-attrs
    
    Fix description: This patch calls slapi_ch_array_free for the
    allocated charray "allowed".