Remove last vestiges of Emerald Hunt behaviour from vanilla SRB2

Was in places the author of this commit needed to look

src/doomstat.h

@@ -763,8 +763,6 @@ extern UINT8 useSeal;
 extern UINT8 use1upSound;
 extern UINT8 maxXtraLife; // Max extra lives from rings
 
-extern mobj_t *hunt1, *hunt2, *hunt3; // Emerald hunt locations
-
 struct exitcondition_t
 {
 	boolean losing;

src/g_game.c

@@ -270,11 +270,6 @@ UINT8 introtoplay;
 UINT8 creditscutscene;
 UINT8 useSeal = 1;
 
-// Emerald locations
-mobj_t *hunt1;
-mobj_t *hunt2;
-mobj_t *hunt3;
-
 tic_t racecountdown, exitcountdown, musiccountdown; // for racing
 exitcondition_t g_exit;
 

src/p_setup.c

@@ -7548,9 +7548,6 @@ static void P_InitLevelSettings(void)
 
 	nummapspraycans = 0;
 
-	// emerald hunt
-	hunt1 = hunt2 = hunt3 = NULL;
-
 	// circuit, race and competition stuff
 	numcheatchecks = 0;
 	timeinmap = 0;