COMPMID-2279: Implement REDUCE_MAX operator for NEON

Change-Id: Iccd25b8aab1dd871c0d86ec3816b1cbf48370066
Signed-off-by: Usama Arif <usama.arif@arm.com>
Reviewed-on: https://review.mlplatform.org/c/1193
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Pablo Marquez <pablo.tello@arm.com>
diff --git a/arm_compute/core/Types.h b/arm_compute/core/Types.h
index 241c1fe..65db06b 100644
--- a/arm_compute/core/Types.h
+++ b/arm_compute/core/Types.h
@@ -561,6 +561,7 @@
     SUM_SQUARE,  /**< Sum of squares */
     SUM,         /**< Sum */
     MIN,         /**< Min */
+    MAX,         /**< Max */
 };
 
 /** Available element-wise operations */