Fix array delete. (rapidsai#202)

Close rapidsai/cuml#3573 .

Authors:
  - Jiaming Yuan (https://github.com/trivialfis)

Approvers:
  - Corey J. Nolet (https://github.com/cjnolet)

URL: rapidsai#202

cpp/include/raft/sparse/linalg/add.cuh

@@ -89,7 +89,7 @@ __global__ void csr_add_calc_row_counts_kernel(
     out_rowcounts[row] = final_size;
     raft::myAtomicAdd(out_rowcounts + m, final_size);
 
-    delete arr;
+    delete[] arr;
   }
 }