GBE/libocl: fix the wrong prototype of scalar native_powr.
GBE/libocl: fix the wrong prototype of scalar native_powr.

Signed-off-by: Zhigang Gong <e04a7b9b70b1e4c6318cf117dcd1a9056e14b97a@intel.com>
Reviewed-by: Junyan He <8f73a735c668918c9613b750d3a88ebf2489599f@linux.intel.com>

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