[wpimath] Add DCMotor factory function for Romi motors (#3319)

wpimath/src/main/native/include/frc/system/plant/DCMotor.h

@@ -149,6 +149,14 @@ class DCMotor {
   static constexpr DCMotor Falcon500(int numMotors = 1) {
     return DCMotor(12_V, 4.69_Nm, 257_A, 1.5_A, 6380_rpm, numMotors);
   }
+
+  /**
+   * Return a gearbox of Romi/TI_RSLK MAX motors.
+   */
+  static constexpr DCMotor RomiBuiltIn(int numMotors = 1) {
+    // From https://www.pololu.com/product/1520/specs
+    return DCMotor(4.5_V, 0.1765_Nm, 1.25_A, 0.13_A, 150_rpm, numMotors);
+  }
 };
 
 }  // namespace frc