Silence warnings on decltype() with Wine 5.22

There were already similar warnings on 32-bit winegcc, but now it also
happens on the 64-bit version. Instead of adding
`-Wno-ignored-attributes` we'll just sprinkle some warning ignores here
and there to prevent any other surprises.

src/wine-host/bridges/vst2.h

@@ -153,6 +153,10 @@ class Vst2Bridge {
      */
     Configuration config;
 
+    // FIXME: This emits `-Wignored-attributes` as of Wine 5.22
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wignored-attributes"
+
     /**
      * The shared library handle of the VST plugin. I sadly could not get
      * Boost.DLL to work here, so we'll just load the VST plugisn by hand.
@@ -160,6 +164,8 @@ class Vst2Bridge {
     std::unique_ptr<std::remove_pointer_t<HMODULE>, decltype(&FreeLibrary)>
         plugin_handle;
 
+#pragma GCC diagnostic pop
+
     /**
      * The loaded plugin's `AEffect` struct, obtained using the above library
      * handle.