libao2 0.8.8-5 doesn't export ao_file_extension

[Florian Scholz]

Hi, the header contains the definition for the function
"ao_file_extension" but the dll doesn't export this function.

exports:

    37: 00001ce0   518 FUNC    GLOBAL DEFAULT   12 ao_initialize
    39: 000012b0   115 FUNC    GLOBAL DEFAULT   12 ao_close
    42: 00001860   127 FUNC    GLOBAL DEFAULT   12 ao_append_option
    43: 000018e0   116 FUNC    GLOBAL DEFAULT   12 ao_shutdown
    47: 000011b0   103 FUNC    GLOBAL DEFAULT   12 ao_driver_id
    49: 00001190    31 FUNC    GLOBAL DEFAULT   12 ao_is_big_endian
    50: 00001220   130 FUNC    GLOBAL DEFAULT   12 ao_default_driver_id
    51: 00001380   180 FUNC    GLOBAL DEFAULT   12 ao_play
    52: 00001760   217 FUNC    GLOBAL DEFAULT   12 ao_open_file
    54: 00001840    31 FUNC    GLOBAL DEFAULT   12 ao_open_live
    55: 00001330    78 FUNC    GLOBAL DEFAULT   12 ao_free_options
    57: 000010f0   100 FUNC    GLOBAL DEFAULT   12 ao_driver_info
    58: 00001160    33 FUNC    GLOBAL DEFAULT   12 ao_driver_info_list