Bug 1850471 - Vendor in the most recent wasm2c rlbox sandbox. r=glandium

Differential Revision: https://phabricator.services.mozilla.com/D187020

config/external/rlbox_wasm2c_sandbox/moz.yaml

@@ -9,8 +9,8 @@ origin:
   description: rlbox integration for the wasm2c sandboxed code
   url: https://github.com/PLSysSec/rlbox_wasm2c_sandbox/tree/upstream-wasm2c
 
-  release: 7e4ff0ebca2c7644a297bfe51a53b9904f0999b2 (2023-04-13T05:07:28Z).
-  revision: 7e4ff0ebca2c7644a297bfe51a53b9904f0999b2
+  release: 0938ae96c5467bdf2210cf21be47ae576cbcc3cd (2023-08-29T00:00:41Z).
+  revision: 0938ae96c5467bdf2210cf21be47ae576cbcc3cd
 
   license: MIT
   license-file: LICENSE

third_party/rlbox_wasm2c_sandbox/include/rlbox_wasm2c_sandbox.hpp

@@ -286,7 +286,7 @@ namespace wasm2c_detail {
 } // namespace wasm2c_detail
 
 // declare the static symbol with weak linkage to keep this header only
-#if defined(_MSC_VER)
+#if defined(_WIN32)
 __declspec(selectany)
 #else
 __attribute__((weak))