COMPMID-1145: (API) Introduce prepare() stage (NEON/CL/GLES)

Change-Id: I5b46764f9c3154ec3e3b9c951cc9e6dfbcb81dfb
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/134255
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
Tested-by: Jenkins <bsgcomp@arm.com>
Reviewed-by: Pablo Tello <pablo.tello@arm.com>
Reviewed-by: Michele DiGiorgio <michele.digiorgio@arm.com>
diff --git a/arm_compute/runtime/NEON/functions/NEDeconvolutionLayer.h b/arm_compute/runtime/NEON/functions/NEDeconvolutionLayer.h
index 66c6d42..3e52716 100644
--- a/arm_compute/runtime/NEON/functions/NEDeconvolutionLayer.h
+++ b/arm_compute/runtime/NEON/functions/NEDeconvolutionLayer.h
@@ -108,6 +108,7 @@
 
     // Inherited methods overridden:
     void run() override;
+    void prepare() override;
 
 private:
     MemoryGroup        _memory_group;
@@ -117,6 +118,7 @@
     ITensor           *_input;
     PadStrideInfo      _info;
     std::pair<unsigned int, unsigned int> _inner_border;
+    bool _is_prepared;
 };
 } // arm_compute
 #endif /* __ARM_COMPUTE_NEDECONVOLUTIONLAYER_H__ */