remove prm air_loop_hvac_set_vsd_curve_type

identical to air_loop_hvac_set_vsd_curve_type in Standards.AirLoopHVAC.rb

lib/openstudio-standards/standards/ashrae_90_1_prm/ashrae_90_1_prm.AirLoopHVAC.rb

@@ -192,12 +192,6 @@ def air_loop_hvac_prm_baseline_economizer_required?(air_loop_hvac, climate_zone)
     return economizer_required
   end
 
-  # Set fan curve for stable baseline to be VSD with fixed static pressure setpoint
-  # @return [string] name of appropriate curve for this code version
-  def air_loop_hvac_set_vsd_curve_type
-    return 'Multi Zone VAV with VSD and Fixed SP Setpoint'
-  end
-
   # Determines if optimum start control is required.
   # PRM does not require optimum start - override it to false.
   #