Hyundai CAN-FD: set available from TCS ACC available (#26921)

* available on TCS signal always

* cmt enh

* better comment

* better

selfdrive/car/hyundai/carstate.py

@@ -201,14 +201,14 @@ class CarState(CarStateBase):
       ret.rightBlindspot = cp.vl["BLINDSPOTS_REAR_CORNERS"]["FR_INDICATOR"] != 0
 
     # cruise state
+    # CAN FD cars enable on main button press, set available if no TCS faults preventing engagement
+    ret.cruiseState.available = cp.vl["TCS"]["ACCEnable"] == 0
     if self.CP.openpilotLongitudinalControl:
       # These are not used for engage/disengage since openpilot keeps track of state using the buttons
-      ret.cruiseState.available = cp.vl["TCS"]["ACCEnable"] == 0
       ret.cruiseState.enabled = cp.vl["TCS"]["ACC_REQ"] == 1
       ret.cruiseState.standstill = False
     else:
       cp_cruise_info = cp_cam if self.CP.flags & HyundaiFlags.CANFD_CAMERA_SCC else cp
-      ret.cruiseState.available = cp_cruise_info.vl["SCC_CONTROL"]["MainMode_ACC"] == 1
       ret.cruiseState.enabled = cp_cruise_info.vl["SCC_CONTROL"]["ACCMode"] in (1, 2)
       ret.cruiseState.standstill = cp_cruise_info.vl["SCC_CONTROL"]["CRUISE_STANDSTILL"] == 1
       ret.cruiseState.speed = cp_cruise_info.vl["SCC_CONTROL"]["VSetDis"] * speed_factor
@@ -484,7 +484,6 @@ class CarState(CarStateBase):
         ("ACCMode", "SCC_CONTROL"),
         ("VSetDis", "SCC_CONTROL"),
         ("CRUISE_STANDSTILL", "SCC_CONTROL"),
-        ("MainMode_ACC", "SCC_CONTROL"),
       ]
       checks += [
         ("SCC_CONTROL", 50),