Fix setting GPU behaviour:

Condition	maxSlotsPerGpu	Behavior
OptimizeModelStr	0	Bypass: non-shared temporary engine
1 GPU	1	Single slot, no round-robin
>1 GPU, VRAM < 24 GB	1	Round-robin: 1 slot per GPU
>1 GPU, VRAM >= 24 GB	-1	Elastic: on-demand slot growth

modules/ANSOCR/ANSRTOCR/RTOCRDetector.cpp

@@ -57,7 +57,7 @@ bool RTOCRDetector::Initialize(const std::string& onnxPath, int gpuId,
             options.maxBatchSize };
         m_engine = EnginePoolManager<float>::instance().acquire(
             m_poolKey, options, onnxPath,
-            kDetSubVals, kDetDivVals, true, -1);
+            kDetSubVals, kDetDivVals, true, getPoolMaxSlotsPerGpu());
         m_usingSharedPool = (m_engine != nullptr);
 
         if (!m_engine) {