MLECO-2082 Fixes and improvements from OOB

  -Fixed noise_reduction CMake bug cause inference to fail when non-default mac_units passed to build script
  -Inference complete message added to noise_reduction LCD
  -Doc update clarfiy vela.ini config file for compiling to non-default memory modes
  -QOL improvement by adding a note on how to make path variables permenant when configuring Arm compilers

Change-Id: Id798b25638260721d8e48468b7a5942bd802d63b
diff --git a/source/use_case/noise_reduction/usecase.cmake b/source/use_case/noise_reduction/usecase.cmake
index 60f92ae..8dfde58 100644
--- a/source/use_case/noise_reduction/usecase.cmake
+++ b/source/use_case/noise_reduction/usecase.cmake
@@ -20,7 +20,7 @@
     STRING)
 
 if (ETHOS_U_NPU_ENABLED)
-    set(DEFAULT_MODEL_PATH      ${DEFAULT_MODEL_DIR}/rnnoise_INT8_vela_${DEFAULT_NPU_CONFIG_ID}.tflite)
+    set(DEFAULT_MODEL_PATH      ${DEFAULT_MODEL_DIR}/rnnoise_INT8_vela_${ETHOS_U_NPU_CONFIG_ID}.tflite)
 else()
     set(DEFAULT_MODEL_PATH      ${DEFAULT_MODEL_DIR}/rnnoise_INT8.tflite)
 endif()