MLECO-2684: Standardize LCD behaviour

* LCD display behavior for Run All now matches Run Next
* Remove repeated code

Signed-off-by: Richard Burton <richard.burton@arm.com>
Change-Id: I16706187fd4e7a59dd935783f5bfb8731435f381
diff --git a/source/use_case/kws/src/UseCaseHandler.cc b/source/use_case/kws/src/UseCaseHandler.cc
index a951e55..3d95753 100644
--- a/source/use_case/kws/src/UseCaseHandler.cc
+++ b/source/use_case/kws/src/UseCaseHandler.cc
@@ -75,8 +75,6 @@
             (arm::app::DsCnnModel::ms_inputRowsIdx > arm::app::DsCnnModel::ms_inputColsIdx)?
              arm::app::DsCnnModel::ms_inputRowsIdx : arm::app::DsCnnModel::ms_inputColsIdx);
 
-        platform.data_psn->clear(COLOR_BLACK);
-
         auto& model = ctx.Get<Model&>("model");
 
         /* If the request has a valid size, set the audio index. */
@@ -137,6 +135,8 @@
         const float secondsPerSample = 1.0/audio::DsCnnMFCC::ms_defaultSamplingFreq;
 
         do {
+            platform.data_psn->clear(COLOR_BLACK);
+
             auto currentIndex = ctx.Get<uint32_t>("clipIndex");
 
             /* Creating a mfcc features sliding window for the data required for 1 inference. */