COMPMID-2322: PRELU support in CLActivationLayer

Change-Id: I3aa8d4964a1861c2b8acef59dc863df7c48f3316
Signed-off-by: giuros01 <giuseppe.rossini@arm.com>
Reviewed-on: https://review.mlplatform.org/c/1146
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/src/core/CL/cl_kernels/elementwise_operation.cl b/src/core/CL/cl_kernels/elementwise_operation.cl
index 0b660e4..42d6d33 100644
--- a/src/core/CL/cl_kernels/elementwise_operation.cl
+++ b/src/core/CL/cl_kernels/elementwise_operation.cl
@@ -38,6 +38,7 @@
 #define SQUARED_DIFF(x, y) (x - y) * (x - y)
 #define DIV(x, y) (x / y)
 #define POWER(x, y) pow(x, y)
+#define PRELU(x, y) (select(y * x, x, x > (DATA_TYPE_OUT)0))
 
 #define OP_FUN_NAME_STR(op) elementwise_operation_##op
 #define OP_FUN_NAME(op) OP_FUN_NAME_STR(op)