Add missing QSYMM8 to GetPixelValue()

* Detected to be missing after adding validation to PadWorkload

Signed-off-by: Tamas Nyiri <tamas.nyiri@arm.com>
Change-Id: I3b2c58f414456008543db299a8461dad5b4d2a96
diff --git a/src/backends/aclCommon/ArmComputeTensorUtils.cpp b/src/backends/aclCommon/ArmComputeTensorUtils.cpp
index 8bbaea7..9ed7b7b 100644
--- a/src/backends/aclCommon/ArmComputeTensorUtils.cpp
+++ b/src/backends/aclCommon/ArmComputeTensorUtils.cpp
@@ -266,6 +266,7 @@
             return arm_compute::PixelValue(static_cast<uint8_t>(pixelValue));
         case arm_compute::DataType::QSYMM16:
             return arm_compute::PixelValue(static_cast<int16_t>(pixelValue));
+        case arm_compute::DataType::QSYMM8:
         case arm_compute::DataType::QASYMM8_SIGNED:
         case arm_compute::DataType::QSYMM8_PER_CHANNEL:
             return arm_compute::PixelValue(static_cast<int8_t>(pixelValue));