Static analyzers complain that a->size is never initialized

wolfcrypt/src/sp_int.c

@@ -4851,7 +4851,7 @@ static void _sp_init_size(sp_int* a, unsigned int size)
 #endif
     _sp_zero((sp_int*)am);
 
-    am->size = size;
+    a->size = size;
 }
 
 /* Initialize the multi-precision number to be zero with a given max size.