Remove "z64" prefix from all headers (#2518)

* z64 - a

* z64 - b

* z64 - c

* z64 - d

* z64 - e

* z64 - f

* z64 - g

* z64 - h

* z64 - i

* z64 - l

* z64 - m

* z64 - o

* z64 - p

* z64 - q

* z64 - r

* z64 - s

* z64 - t

* z64 - v

* restore file

* fix merge

* fix merge

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Co-authored-by: Dragorn421 <Dragorn421@users.noreply.github.com>

src/code/z_env_flags.c

@@ -1,7 +1,7 @@
 #include "array_count.h"
 #include "ultra64.h"
-#include "z64cutscene_flags.h"
-#include "z64play.h"
+#include "cutscene_flags.h"
+#include "play_state.h"
 
 void CutsceneFlags_UnsetAll(PlayState* play) {
     u8 i;