Fix T96925: Fast diagonal movement in walk navigation

View moves faster with two active directions.
This is probably because `dvec` is not normalized when moving in two directions.
Normalizing this direction vector will fix the problem.

Differential Revision: https://developer.blender.org/D14729

source/blender/editors/space_view3d/view3d_navigate_walk.c

@@ -1205,7 +1205,6 @@ static int walkApply(bContext *C, WalkInfo *walk, bool is_confirm)
             dvec_tmp[2] = 0.0f;
           }
 
-          normalize_v3(dvec_tmp);
           add_v3_v3(dvec, dvec_tmp);
         }
 
@@ -1226,7 +1225,6 @@ static int walkApply(bContext *C, WalkInfo *walk, bool is_confirm)
           dvec_tmp[1] = direction * rv3d->viewinv[0][1];
           dvec_tmp[2] = 0.0f;
 
-          normalize_v3(dvec_tmp);
           add_v3_v3(dvec, dvec_tmp);
         }
 
@@ -1249,6 +1247,8 @@ static int walkApply(bContext *C, WalkInfo *walk, bool is_confirm)
           }
         }
 
+        normalize_v3(dvec);
+
         /* apply movement */
         mul_v3_fl(dvec, walk->speed * time_redraw);
       }