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.

tests/wamr-test-suites/spec-test-script/thread_proposal_ignore_cases.patch

@@ -211,6 +211,21 @@ index 1ea2b06..8eded37 100644
  (assert_return (invoke $module1 "call-8") (i32.const 69))
  (assert_return (invoke $module1 "call-9") (i32.const 70))
 +;)
+diff --git a/test/core/table.wast b/test/core/table.wast
+index 0bc43ca6..ee5209ec 100644
+--- a/test/core/table.wast
++++ b/test/core/table.wast
+@@ -8,8 +8,8 @@
+ (module (table 0 65536 funcref))
+ (module (table 0 0xffff_ffff funcref))
+ 
+-(assert_invalid (module (table 0 funcref) (table 0 funcref)) "multiple tables")
+-(assert_invalid (module (table (import "spectest" "table") 0 funcref) (table 0 funcref)) "multiple tables")
++(module (table 0 funcref) (table 0 funcref))
++(module (table (import "spectest" "table") 0 funcref) (table 0 funcref))
+ 
+ (assert_invalid (module (elem (i32.const 0))) "unknown table")
+ (assert_invalid (module (elem (i32.const 0) $f) (func $f)) "unknown table")
 diff --git a/test/core/thread.wast b/test/core/thread.wast
 index c3456a6..83fc281 100644
 --- a/test/core/thread.wast
@@ -228,3 +243,23 @@ index c3456a6..83fc281 100644
  (wait $T1)
  (wait $T2)
 +;)
+diff --git a/test/core/unreached-invalid.wast b/test/core/unreached-invalid.wast
+index 6ef4ac55..9a2387a3 100644
+--- a/test/core/unreached-invalid.wast
++++ b/test/core/unreached-invalid.wast
+@@ -535,6 +535,7 @@
+   ))
+   "type mismatch"
+ )
++(; invalid case, the module is fine for the latest spec interpreter
+ (assert_invalid
+   (module (func $type-br_table-label-num-vs-label-num-after-unreachable
+     (block (result f64)
+@@ -549,6 +550,7 @@
+   ))
+   "type mismatch"
+ )
++;)
+ 
+ (assert_invalid
+   (module (func $type-block-value-nested-unreachable-num-vs-void