bench: update benchmarks

Author: gunjjoshi

lib/node_modules/@stdlib/math/base/special/riemann-zeta/benchmark/c/cephes/benchmark.c

@@ -95,18 +95,15 @@ static double rand_double( void ) {
 */
 static double benchmark( void ) {
 	double elapsed;
-	double x[ 100 ];
+	double x;
 	double y;
 	double t;
 	int i;
 
-	for ( i = 0; i < 100; i++ ) {
-		x[ i ] = ( 56.0 * rand_double() ) + 1.1;
-	}
-
 	t = tic();
 	for ( i = 0; i < ITERATIONS; i++ ) {
-		y = zeta( x[ i % 100 ], 1.0 );
+		x = ( 56.0*rand_double() ) + 1.1;
+		y = zeta( x, 1.0 );
 		if ( y != y ) {
 			printf( "should not return NaN\n" );
 			break;