gc.c: remove unused `struct`s from `RVALUE`.
MODIFY
src/gc.c
src/gc.c
@@ -134,12 +134,6 @@ typedef struct {
struct RFiber fiber;
struct RException exc;
struct RBreak brk;
-#ifdef MRB_WORD_BOXING
-#ifndef MRB_NO_FLOAT
- struct RFloat floatv;
-#endif
- struct RCptr cptr;
-#endif
} as;
} RVALUE;

gc.c: remove unused `struct`s from `RVALUE`.