Timing adapter fix, init constructor priority

The timing adapters are attached to the Ethos-U AXI ports and should
only be initialized if the platform has been built with NPU support.

Add priority to init the constructor, insuring it will run before
any other constructor. This is important because the init constructor
sets up UART.

Change-Id: I189687437b95b11f6503c7631720e7883c24ada6
diff --git a/targets/corstone-300/CMakeLists.txt b/targets/corstone-300/CMakeLists.txt
index 5dc3804..7c8db4e 100644
--- a/targets/corstone-300/CMakeLists.txt
+++ b/targets/corstone-300/CMakeLists.txt
@@ -124,9 +124,8 @@
     target.cpp)
 
 target_link_libraries(ethosu_target_startup INTERFACE
-    $<$<TARGET_EXISTS:ethosu_core_driver>:ethosu_core_driver>
+    $<$<TARGET_EXISTS:ethosu_core_driver>:ethosu_core_driver;timing_adapter>
     mpu
-    timing_adapter
     ethosu_mhu_dummy
     ethosu_uart_cmsdk_apb)