Increase size of lv2 atom output buffer by 32x, within limits

This buffer is used for the UI thread, which runs slower than RT.
The buffer can fill very quickly, and it's only cleared during
the main thread.
So, increase this buffer in a reasonable amount to compensate.

This allows to run the new LSP plugin UIs.

source/backend/plugin/CarlaPluginLV2.cpp

@@ -2329,7 +2329,7 @@ public:
 
         if (fExt.worker != nullptr || (fUI.type != UI::TYPE_NULL && fEventsOut.count > 0 && (fEventsOut.data[0].type & CARLA_EVENT_DATA_ATOM) != 0))
         {
-            fAtomBufferOut.createBuffer(eventBufferSize);
+            fAtomBufferOut.createBuffer(std::min(eventBufferSize*32, 1638400U));
             fTmpAtomBuffer = new uint8_t[fAtomBufferOut.getSize()];
         }
 
@@ -2693,12 +2693,12 @@ public:
 
         if (pData->needsReset)
         {
-            uint8_t midiData[3] = { 0, 0, 0 };
-
             if (fEventsIn.ctrl != nullptr && (fEventsIn.ctrl->type & CARLA_EVENT_TYPE_MIDI) != 0)
             {
                 const uint32_t j = fEventsIn.ctrlIndex;
-                CARLA_SAFE_ASSERT(j < fEventsIn.count);
+                CARLA_ASSERT(j < fEventsIn.count);
+
+                uint8_t midiData[3] = { 0, 0, 0 };
 
                 if (pData->options & PLUGIN_OPTION_SEND_ALL_SOUND_OFF)
                 {