Reuse request on Wine side during VST2 processing

The object was constantly being recreated, resulting in memory
allocations caused by creating and destroying the audio buffer vectors.

CHANGELOG.md

@@ -30,6 +30,8 @@ Versioning](https://semver.org/spec/v2.0.0.html).
 - Redesigned the VST3 audio socket handling to be able to reuse the process data
   objects on both sides. This greatly reduces the overhead of our VST3 bridging
   by getting rid of all memory allocations during audio processing.
+- VST2 audio processing also received the same optimizations. In a few places
+  yabridge would still reallocate heap data during audio processing.
 - Considerably optimized both VST2 and VST3 audio processing by preventing
   unnecessary memory operations. As it turns out, the underlying binary
   serialization library used by yabridge would always reinitialize the type-safe