split unrelated code

src/code_080300AC.c

@@ -0,0 +1,25 @@
+#include "global.h"
+#include "entity.h"
+#include "functions.h"
+
+//extern void DmaZero(void*, u32);
+
+typedef struct {
+    u16 unk0;
+    u16 filler2[32];
+    u16 unk66;
+} struct_0300110C;
+
+extern struct_0300110C gUnk_0300110C;
+
+void sub_080300AC(void) {
+  _DmaZero(&gUnk_0300110C.unk0, 0x44);
+  gUnk_0300110C.unk66 = 0xff;
+}
+
+void sub_080300C4(void) {
+  if (gScreenTransition.field_0xae == 0xff) {
+    gScreenTransition.field_0xac = 0;
+    _DmaZero(&gScreenTransition.field_0x4c[32], 0x40);
+  }
+}