StagingBuffer: Large slots should be aligned to alignment

Slots whose stride size is larger than the slot alignment value
should have their size rounded up to the alignment size so that
the slots that follow them will also be aligned.

include/user/stimulusFrame.h

@@ -96,7 +96,7 @@ public:
 				+ ": StimulusFrame: failed to create clBuffer");
 		}
 
-		std::cout << __func__ << ": StimulusFrame: created clBuffer with size " << slotDesc.nBytes << " bytes @ " << (const void*)slotDesc.vaddr << std::endl;
+//		std::cout << __func__ << ": StimulusFrame: created clBuffer with size " << slotDesc.nBytes << " bytes @ " << (const void*)slotDesc.vaddr << std::endl;
 	}
 
 	~StimulusFrame() = default;