CocoaSpice: fix various issues

- port: fix use after free when writing data
- display: mitigate deadlock on scanout texture
- port: fix race when writing to cache buffer

Fixes #5205

UTM.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved

@@ -16,7 +16,7 @@
       "location" : "https://github.com/utmapp/CocoaSpice.git",
       "state" : {
         "branch" : "main",
-        "revision" : "409f78bc17943980e5920c83dc210bfd62f77a1a"
+        "revision" : "bbcc6371874fee17ac620176b9680393fc9a18ac"
       }
     },
     {