bench: refactor to use dynamic memory allocation in strided/base/smap

PR-URL: #9353
Ref: #8643
Reviewed-by: Athan Reines <kgryte@gmail.com>

Author: Omar-2718

lib/node_modules/@stdlib/strided/base/smap/benchmark/c/benchmark.length.c

@@ -106,11 +106,13 @@ static float identity( const float x ) {
 */
 static double benchmark( int iterations, int len ) {
 	double elapsed;
-	float x[ len ];
-	float y[ len ];
+	float *x;
+	float *y;
 	double t;
 	int i;
 
+	x = (float *)malloc( len * sizeof( float ) );
+	y = (float *)malloc( len * sizeof( float ) );
 	for ( i = 0; i < len; i++ ) {
 		x[ i ] = ( rand_float()*200.0f ) - 100.0f;
 		y[ i ] = 0.0f;
@@ -128,6 +130,8 @@ static double benchmark( int iterations, int len ) {
 	if ( y[ i%len ] != y[ i%len ] ) {
 		printf( "should not return NaN\n" );
 	}
+	free( x );
+	free( y );
 	return elapsed;
 }