Remove trailing whitespaces in vla.c that was missed previously

cmake/vla.c

 int main() {
-    static int x; 
-    char a[++x]; 
-    a[sizeof a - 1] = 0; 
-    int N; 
+    static int x;
+    char a[++x];
+    a[sizeof a - 1] = 0;
+    int N;
     return a[0];
 }
\ No newline at end of file