fix a few warnings

src/battle_bg/battle_bg_hook.s

 	bx r1
 bxr0:
 	bx r0
-*/
+*/

src/dns/dns_core.c

 void dns_apply_lighting(void* blockset, u8 secondary, struct color* buffer) {
     if (dns_get_time_of_day() != NIGHT)
         return;
-    for (int i = 0; i < (sizeof (lightmap) / sizeof (lightmap[0])); ++i) {
+    for (unsigned int i = 0; i < (sizeof (lightmap) / sizeof (lightmap[0])); ++i) {
         if (blockset == lightmap[i].blockset) {
             buffer[(lightmap[i].pal - (secondary ? 7 : 0)) * 16 + lightmap[i].index] = lightmap[i].color;
         }
     tint_palette(pal_slot);
     dns_apply_shaders(pal_slot + 16, 1, palette_unfaded_buffer);
 }
-/*use fade in animation, load palettes according to current fade state*/
+/*use fade in animation, load palettes according to current fade state*/

src/savefile/flag_manipulation.c

 */
 #include <pokeagb/pokeagb.h>
 
+#include <agb_debug.h>
+
 #define TRAINER_FLAG_SPACE_START 0x1000
 
 extern u16 tb_modify_flag_id(u16 flag_id);
     u16 val = script_read_halfword(env);
     var_set_hack(var, val);
     return 0;
-}
+}