COMPMID-1166: Fixed alpha/beta mixup for some merges.

The default templated merge, and the specialised S8 12x8 merge, were
using alpha and beta the wrong way round.  Fixed.

Change-Id: Ie559b665edf1eb012e8cb54ea0bca31612bcc072
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/131309
Tested-by: Jenkins <bsgcomp@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
diff --git a/src/runtime/NEON/functions/NEGEMMLowpAssemblyMatrixMultiplyCore.cpp b/src/runtime/NEON/functions/NEGEMMLowpAssemblyMatrixMultiplyCore.cpp
index bd81bf2..98b4767 100644
--- a/src/runtime/NEON/functions/NEGEMMLowpAssemblyMatrixMultiplyCore.cpp
+++ b/src/runtime/NEON/functions/NEGEMMLowpAssemblyMatrixMultiplyCore.cpp
@@ -58,13 +58,13 @@
     {
         case DataType::S8:
         {
-            run_optimised = setup_assembly_kernel(a, b, output, 1.f, 1.f, true, _workspace, _B_pretransposed, _memory_group, _asm_glue_signed);
+            run_optimised = setup_assembly_kernel(a, b, output, 1.f, 0.f, true, _workspace, _B_pretransposed, _memory_group, _asm_glue_signed);
             break;
         }
         case DataType::QASYMM8:
         case DataType::U8:
         {
-            run_optimised = setup_assembly_kernel(a, b, output, 1.f, 1.f, true, _workspace, _B_pretransposed, _memory_group, _asm_glue_unsigned);
+            run_optimised = setup_assembly_kernel(a, b, output, 1.f, 0.f, true, _workspace, _B_pretransposed, _memory_group, _asm_glue_unsigned);
             break;
         }
         default: