AP_Math: remove normalization of random compass Vector3f

libraries/AP_Math/AP_Math.cpp

@@ -348,17 +348,14 @@ float rand_float(void)
 #endif
 }
 
+// generate a random Vector3f with each value between -1.0 and 1.0
 Vector3f rand_vec3f(void)
 {
-    Vector3f v {
+    return Vector3f{
         rand_float(),
         rand_float(),
         rand_float()
     };
-    if (!v.is_zero()) {
-        v.normalize();
-    }
-    return v;
 }
 #endif