IVGCVSW-2691 Add Serialize/Deseralize Gather layer

Change-Id: I589d37c9f65801b701858d6e68e2e3151fac6e16
Signed-off-by: Saoirse Stewart <saoirse.stewart@arm.com>
diff --git a/src/armnnSerializer/ArmnnSchema.fbs b/src/armnnSerializer/ArmnnSchema.fbs
index ed3de83..ac32e66 100644
--- a/src/armnnSerializer/ArmnnSchema.fbs
+++ b/src/armnnSerializer/ArmnnSchema.fbs
@@ -108,7 +108,8 @@
     Greater = 24,
     ResizeBilinear = 25,
     Subtraction = 26,
-    StridedSlice = 27
+    StridedSlice = 27,
+    Gather = 28
 }
 
 // Base layer table to be used as part of other layers
@@ -188,6 +189,10 @@
     transposeWeightsMatrix:bool = false;
 }
 
+table GatherLayer {
+    base:LayerBase;
+}
+
 table GreaterLayer {
     base:LayerBase;
 }
@@ -427,7 +432,8 @@
     GreaterLayer,
     ResizeBilinearLayer,
     SubtractionLayer,
-    StridedSliceLayer
+    StridedSliceLayer,
+    GatherLayer
 }
 
 table AnyLayer {