Fix clang compile error

cub/block/radix_rank_sort_operations.cuh

@@ -117,7 +117,7 @@ struct BFEDigitExtractor : BaseDigitExtractor<KeyT>
 
     __device__ __forceinline__ uint32_t Digit(UnsignedBits key)
     {
-        return BFE(ProcessFloatMinusZero(key), bit_start, num_bits);
+        return BFE(this->ProcessFloatMinusZero(key), bit_start, num_bits);
     }
 };
 
@@ -136,7 +136,7 @@ struct ShiftDigitExtractor : BaseDigitExtractor<KeyT>
 
     __device__ __forceinline__ uint32_t Digit(UnsignedBits key)
     {
-        return uint32_t(ProcessFloatMinusZero(key) >> UnsignedBits(bit_start)) & mask;
+        return uint32_t(this->ProcessFloatMinusZero(key) >> UnsignedBits(bit_start)) & mask;
     }
 };