COMPMID-3304: Update OpenCL GEMM heuristic for Int8

Change-Id: I6b7ff678d8d0437a1639db2ff602ea1cdb155464
Signed-off-by: Gian Marco Iodice <gianmarco.iodice@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/3056
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
diff --git a/arm_compute/core/CL/gemm/native/CLGEMMNativeKernelConfiguration.h b/arm_compute/core/CL/gemm/native/CLGEMMNativeKernelConfiguration.h
index fced41b..a6341e5 100644
--- a/arm_compute/core/CL/gemm/native/CLGEMMNativeKernelConfiguration.h
+++ b/arm_compute/core/CL/gemm/native/CLGEMMNativeKernelConfiguration.h
@@ -26,6 +26,7 @@
 
 #include "arm_compute/core/CL/ICLGEMMKernelConfiguration.h"
 #include "arm_compute/core/CL/gemm/native/CLGEMMNativeKernelConfigurationBifrost.h"
+#include "arm_compute/core/CL/gemm/native/CLGEMMNativeKernelConfigurationMidgard.h"
 #include "arm_compute/core/CL/gemm/native/CLGEMMNativeKernelConfigurationValhall.h"
 
 #include <memory>
@@ -49,12 +50,11 @@
         switch(get_arch_from_target(gpu))
         {
             case GPUTarget::MIDGARD:
+                return support::cpp14::make_unique<CLGEMMNativeKernelConfigurationMidgard>(gpu);
             case GPUTarget::BIFROST:
                 return support::cpp14::make_unique<CLGEMMNativeKernelConfigurationBifrost>(gpu);
-                break;
             case GPUTarget::VALHALL:
                 return support::cpp14::make_unique<CLGEMMNativeKernelConfigurationValhall>(gpu);
-                break;
             default:
                 ARM_COMPUTE_ERROR("Not supported GPU target");
         }