Update ArmNN README with doxygen information

Signed-off-by: Nikhil Raj <nikhil.raj@arm.com>
Change-Id: I3ac729efba4945868710e2a233646f9634470967
diff --git a/README.md b/README.md
index 8766d3f..15c527e 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,8 @@
 
 API Documentation is available at https://github.com/ARM-software/armnn/wiki/Documentation.
 
+Dox files to generate Arm NN doxygen files can be found at armnn/docs/. Following generation the xhtml files can be found at armnn/documentation/
+
 ### Build Instructions
 
 Arm tests the build system of Arm NN with the following build environments: