Remove extra semi colon from faiss/utils/distances_simd.cpp

Summary:
`-Wextra-semi` or `-Wextra-semi-stmt`

If the code compiles, this is safe to land.

Reviewed By: algoriddle

Differential Revision: D52965948

fbshipit-source-id: e24e38ecbb7e0c957b024a1ae7b2ec94d2fa0adf

Author: r-barnes

faiss/utils/distances_simd.cpp

@@ -969,7 +969,6 @@ void fvec_L2sqr_ny_y_transposed_D(
 
     // squared length of x
     float x_sqlen = 0;
-    ;
     for (size_t j = 0; j < DIM; j++) {
         x_sqlen += x[j] * x[j];
     }