longitudinal_planner.py: cleaner variable assignment (#29290)

* cleaner variable assignment

* Update selfdrive/controls/lib/longitudinal_planner.py

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Co-authored-by: Adeeb Shihadeh <adeebshihadeh@gmail.com>

selfdrive/controls/lib/longitudinal_planner.py

@@ -94,8 +94,7 @@ class LongitudinalPlanner:
     self.mpc.mode = 'blended' if sm['controlsState'].experimentalMode else 'acc'
 
     v_ego = sm['carState'].vEgo
-    v_cruise_kph = sm['controlsState'].vCruise
-    v_cruise_kph = min(v_cruise_kph, V_CRUISE_MAX)
+    v_cruise_kph = min(sm['controlsState'].vCruise, V_CRUISE_MAX)
     v_cruise = v_cruise_kph * CV.KPH_TO_MS
 
     long_control_off = sm['controlsState'].longControlState == LongCtrlState.off