Qt player selection dialog

During role/race/gender/alignment selection, when gender gets toggled
replace the gender-specific role titles and their icons to reflect
new gender value.  And enable or disable Valkyrie choice depending
upon the gender value, not just current race value.

This ended up revising a lot of the NetHackQtPlayerSelector code,
eliminating some redundancies and being more careful with the use of
validrace()/validgend()/validalign().  That still isn't bulletproof.

It also changes the two instances of buttonPressed that were drawing
Qt6 warnings from connect() at run-time with buttonClicked.  That
works as intended with Qt5 and might eliminate those.

The code to use female player character tiles looks correct to me
but when I toggle gender, role titles change but their icons don't.
I don't know what's going on here.  Some ealier code always specifies
MALE but that code isn't used according to various prints to stderr
that I temporarily inserted.

win/Qt/qt_plsel.h

@@ -24,6 +24,9 @@ public slots:
         void Randomize();
         void plnamePlayVsQuit();
 
+        void populate_roles();
+        void populate_races();
+
 	void selectName(const QString& n);
 	void selectRole(int current, int, int previous, int);
 	void selectRace(int current, int, int previous, int);
@@ -43,6 +46,8 @@ private:
 	bool fully_specified_role;
         int chosen_gend;
         int chosen_align;
+        int cleric_role_row;
+        int human_race_row;
 
         QPushButton *rand_btn;
         QPushButton *play_btn;