COMPMID-1393: Update example documentation

Change-Id: I7251575645b35b611de9d8931bb2b7dbc096de13
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/140544
Tested-by: Jenkins <bsgcomp@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
diff --git a/examples/graph_lenet.cpp b/examples/graph_lenet.cpp
index c02e2f9..0d8a943 100644
--- a/examples/graph_lenet.cpp
+++ b/examples/graph_lenet.cpp
@@ -126,8 +126,10 @@
 
 /** Main program for LeNet
  *
+ * @note To list all the possible arguments execute the binary appended with the --help option
+ *
  * @param[in] argc Number of arguments
- * @param[in] argv Arguments ( [optional] Target (0 = NEON, 1 = OpenCL, 2 = OpenCL with Tuner), [optional] Path to the weights folder, [optional] batches, [optional] Fast math for convolution layer (0 = DISABLED, 1 = ENABLED) )
+ * @param[in] argv Arguments
  */
 int main(int argc, char **argv)
 {