Follow up r15936 Fixed crash when sc_increaseagi would be cast on non-players.

git-svn-id: https://svn.code.sf.net/p/rathena/svn/trunk@15944 54d463be-8e91-2dee-dedb-b68131a5f0ec

src/map/status.c

@@ -5939,7 +5939,7 @@ int status_change_start(struct block_list* bl,enum sc_type type,int rate,int val
 			return 0;
 	
 	case SC_INCREASEAGI:
-		 if(pc_issit(sd)){ 
+		 if(sd && pc_issit(sd)){ 
 			 pc_setstand(sd);
 			 clif_status_load(&sd->bl,SI_SIT,0);
 		 }