Implement GC (Garbage Collection) feature for interpreter, AOT and LLVM-JIT (#3125)

Implement the GC (Garbage Collection) feature for interpreter mode,
AOT mode and LLVM-JIT mode, and support most features of the latest
spec proposal, and also enable the stringref feature.

Use `cmake -DWAMR_BUILD_GC=1/0` to enable/disable the feature,
and `wamrc --enable-gc` to generate the AOT file with GC supported.

And update the AOT file version from 2 to 3 since there are many AOT
ABI breaks, including the changes of AOT file format, the changes of
AOT module/memory instance layouts, the AOT runtime APIs for the
AOT code to invoke and so on.

core/iwasm/compilation/aot_emit_function.h

@@ -30,6 +30,12 @@ bool
 aot_compile_op_ref_func(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx,
                         uint32 func_idx);
 
+#if WASM_ENABLE_GC != 0
+bool
+aot_compile_op_call_ref(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx,
+                        uint32 type_idx, bool tail_call);
+#endif
+
 #ifdef __cplusplus
 } /* end of extern "C" */
 #endif