[Thermo] Fix inconsistencies in PDSS_IonsFromNeutral

The definitions of p0, Tmin, and Tmax were circular -- they queried the
STITbyPDSS object which just referenced the same PDSS_IonsFromNeutral
object. Instead, pull these properties from the associated "neutral molecule"
phase.

The overrides of setTemperature and temperature were unnecessary and likely to
cause problems.

include/cantera/thermo/PDSS_IonsFromNeutral.h

@@ -102,8 +102,6 @@ class PDSS_IonsFromNeutral : public PDSS_Nondimensional
     //! @name Mechanical Equation of State Properties
     //! @{
 
-    virtual void setTemperature(doublereal temp);
-    virtual doublereal temperature() const;
     virtual void setState_TP(doublereal temp, doublereal pres);
     virtual void setState_TR(doublereal temp, doublereal rho);
 

src/thermo/PDSS_IonsFromNeutral.cpp

@@ -94,9 +94,9 @@ void PDSS_IonsFromNeutral::constructPDSSXML(VPStandardStateTP* tp, size_t spinde
 void PDSS_IonsFromNeutral::initThermo()
 {
     PDSS::initThermo();
-    m_p0 = m_tp->speciesThermo().refPressure(m_spindex);
-    m_minTemp = m_spthermo->minTemp(m_spindex);
-    m_maxTemp = m_spthermo->maxTemp(m_spindex);
+    m_p0 = neutralMoleculePhase_->refPressure();
+    m_minTemp = neutralMoleculePhase_->minTemp();
+    m_maxTemp = neutralMoleculePhase_->maxTemp();
 }
 
 doublereal PDSS_IonsFromNeutral::enthalpy_RT() const
@@ -231,19 +231,6 @@ doublereal PDSS_IonsFromNeutral::molarVolume_ref() const
     return val;
 }
 
-doublereal PDSS_IonsFromNeutral::temperature() const
-{
-    // Obtain the temperature from the owning VPStandardStateTP object if you
-    // can.
-    m_temp = m_tp->temperature();
-    return m_temp;
-}
-
-void PDSS_IonsFromNeutral::setTemperature(doublereal temp)
-{
-    m_temp = temp;
-}
-
 void PDSS_IonsFromNeutral::setState_TP(doublereal temp, doublereal pres)
 {
     m_pres = pres;