longitudinal_planner: Convert self.mode to a local variable in update() (#35999)

Make 'mode' variable local

selfdrive/controls/lib/longitudinal_planner.py

@@ -90,7 +90,7 @@ class LongitudinalPlanner:
     return x, v, a, j, throttle_prob
 
   def update(self, sm):
-    self.mode = 'blended' if sm['selfdriveState'].experimentalMode else 'acc'
+    mode = 'blended' if sm['selfdriveState'].experimentalMode else 'acc'
 
     if len(sm['carControl'].orientationNED) == 3:
       accel_coast = get_coast_accel(sm['carControl'].orientationNED[1])
@@ -113,7 +113,7 @@ class LongitudinalPlanner:
     # No change cost when user is controlling the speed, or when standstill
     prev_accel_constraint = not (reset_state or sm['carState'].standstill)
 
-    if self.mode == 'acc':
+    if mode == 'acc':
       accel_clip = [ACCEL_MIN, get_max_accel(v_ego)]
       steer_angle_without_offset = sm['carState'].steeringAngleDeg - sm['liveParameters'].angleOffsetDeg
       accel_clip = limit_accel_in_turns(v_ego, steer_angle_without_offset, accel_clip, self.CP)
@@ -163,7 +163,7 @@ class LongitudinalPlanner:
     output_a_target_e2e = sm['modelV2'].action.desiredAcceleration
     output_should_stop_e2e = sm['modelV2'].action.shouldStop
 
-    if self.mode == 'acc':
+    if mode == 'acc':
       output_a_target = output_a_target_mpc
       self.output_should_stop = output_should_stop_mpc
     else: