avcodec/wma: Use avpriv_float_dsp_alloc()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/libmp3lame: Use avpriv_float_dsp_alloc()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/atrac3: Use avpriv_float_dsp_alloc()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>