fix incomplete specification of primary attack skill

src/player.c

@@ -1,5 +1,6 @@
 #include "player.h"
 #include "item.h"
+#include "aoe.h"
 #include <gint/defs/util.h>
 
 static int xp_to_next_level(int level)
@@ -48,6 +49,8 @@ void player_compute_skills(entity_t *e, int *equips, int *skills)
 
     for(int i = 0; i < 6; i++)
         skills[i] = -1;
+    /* Default attack */
+    skills[0] = AOE_SLASH;
 
     /* Sword/staff */
     if(equips[0] >= 0)