PreparedModel: use flush instead of update

The update() function was removed in S branch, transition to using the
flush() function instead.

Transition seemed to be in commit: Ia047d0698d56c83977b816cd38857d3b75b969d5

Test: local build

Change-Id: I91ecb5d358be4721a1ccf0031541ac7c1b50f40a

ArmnnPreparedModel.cpp

diff --git a/ArmnnPreparedModel.cpp b/ArmnnPreparedModel.cpp
index 0899430..2417843 100644
--- a/ArmnnPreparedModel.cpp
+++ b/ArmnnPreparedModel.cpp
@@ -279,7 +279,7 @@
     // this is simpler and is what the CpuExecutor does.
     for (android::nn::RunTimePoolInfo& pool : *pMemPools)
     {
-        pool.update();
+        pool.flush();
     }
 
     cb.callback(ErrorStatus::NONE, "ExecuteGraph");

ArmnnPreparedModel_1_2.cpp

diff --git a/ArmnnPreparedModel_1_2.cpp b/ArmnnPreparedModel_1_2.cpp
index 84ff6e2..8ce82f1 100644
--- a/ArmnnPreparedModel_1_2.cpp
+++ b/ArmnnPreparedModel_1_2.cpp
@@ -375,7 +375,7 @@
     // this is simpler and is what the CpuExecutor does.
     for (android::nn::RunTimePoolInfo& pool : *pMemPools)
     {
-        pool.update();
+        pool.flush();
     }
     ALOGV("ArmnnPreparedModel_1_2::executeSynchronously() after Execution");
 
@@ -571,7 +571,7 @@
     // this is simpler and is what the CpuExecutor does.
     for (android::nn::RunTimePoolInfo& pool : *pMemPools)
     {
-        pool.update();
+        pool.flush();
     }
 
     if (cb.measureTiming == MeasureTiming::YES)