Fixed issue in niflheim quest where the script set a variable not related to the quest at all (bugreport:4104).

Added check in Knight job change test to prevent repeating the quest (bugreport:4099).

git-svn-id: https://svn.code.sf.net/p/rathena/svn/trunk@15292 54d463be-8e91-2dee-dedb-b68131a5f0ec

npc/cities/niflheim.txt

@@ -245,7 +245,7 @@ niflheim,350,258,1	script	Cursed Spirit#nif	802,{
 			switch(rand(1,5)) {
 			case 1:
 				if (morison_meat < 15) {
-					set MISC_QUEST,MISC_QUEST | 1;
+					set morrison_meat,15;
 					mes "[Ashe Bruce]";
 					mes "You... You broke the curse!";
 					mes "How did you know that spell?!";

npc/jobs/2-1/knight.txt

@@ -1223,14 +1223,18 @@ prt_in,79,94,4	script	Sir Windsor#knt	733,{
 			mes ".....What?";
 			next;
 		}
-		else 
+		else {
 			set .@mes$,"I want to try again!:...";
+			next;
+		}
 		if (select(.@mes$) == 1) {
 			mes "[Sir Windsor]";
 			mes "...";
 			next;
 			set KNIGHT_Q,7;
-			changequest 9004,9005;
+			if (checkquest(9004) != -1) {
+				changequest 9004,9005;
+			}
 			mes "[Sir Windsor]";
 			mes "...";
 			mes "......";