Reduce overlay dependencies on global.h (8) (#2478)

* move variables into z64environment.h

* z_room.h

* z64sram.h, z64ss_sram.h, z64font.h, kanread.h

* z64lifemeter.h, z64debug.h, debug_arena.h

* buffers.h

* remove z_bgcheck global

* gamealloc.h

* suggestions

* .bdd

src/code/debug_malloc.c

@@ -1,5 +1,7 @@
-#include "global.h"
 #include "libc64/os_malloc.h"
+#include "debug_arena.h"
+
+#include "macros.h"
 
 #define LOG_SEVERITY_NOLOG 0
 #define LOG_SEVERITY_ERROR 2