[wasm] Turn on all wasm instructions on 64bit platforms.

R=titzer@chromium.org

Review URL: https://codereview.chromium.org/1514913003

Cr-Commit-Position: refs/heads/master@{#32807}

src/wasm/wasm-opcodes.cc

@@ -115,13 +115,12 @@ bool WasmOpcodes::IsSupported(WasmOpcode opcode) {
     case kExprF32UConvertI64:
     case kExprF64SConvertI64:
     case kExprF64UConvertI64:
-
-#endif
-
     case kExprI64SConvertF32:
     case kExprI64SConvertF64:
     case kExprI64UConvertF32:
     case kExprI64UConvertF64:
+
+#endif
       return false;
     default:
       return true;