Support inferences with multiple inputs and outputs

Build flatbuffers library.

Update network class to extract IFM and OFM dimensions from the tflite
file.

Update the uapi and core apis to support up to 16 IFM and OFM buffers
per inference.

Change-Id: I2f2f177aa4c2d5f9f50f23eb33c44e01ec2cbe09
diff --git a/driver_library/CMakeLists.txt b/driver_library/CMakeLists.txt
index 4d9001f..4444357 100644
--- a/driver_library/CMakeLists.txt
+++ b/driver_library/CMakeLists.txt
@@ -28,6 +28,7 @@
 target_include_directories(ethosu PUBLIC "include")
 set_target_properties(ethosu PROPERTIES PUBLIC_HEADER "include/ethosu.hpp")
 set_target_properties(ethosu PROPERTIES VERSION ${PROJECT_VERSION})
+target_link_libraries(ethosu PRIVATE flatbuffers)
 
 # Install library and public headers
 install(TARGETS ethosu