hcrypto: Fix performance regression

lib/hcrypto/libtommath/bn_s_mp_montgomery_reduce_fast.c

@@ -31,14 +31,6 @@ mp_err s_mp_montgomery_reduce_fast(mp_int *x, const mp_int *n, mp_digit rho)
       }
    }
 
-   /*
-    * We only have to initialize W[] here because even though we'll initialize
-    * it below, scan-build can fail to notice that we initialized as much of it
-    * as we'll use, and so it emits a spurious warning.  An optimizing compiler
-    * might be as dumb as scan-build... so let's avoid the danger.
-    */
-   MP_ZERO_BUFFER(W, sizeof(W));
-
    /* first we have to get the digits of the input into
     * an array of double precision words W[...]
     */