NNAPI systrace for timing statistics

This adds systrace tracing to NNAPI. The tracing
will be helpful for:
- getting numbers on where time is spent currently
- diagnosing and improving performance
- benchmarking

TODOs:
- Write analysis tools for traces

Change-Id: I9026f1043428cb715b577901bec3a2e1e39a82e3
Merged-In: I9026f1043428cb715b577901bec3a2e1e39a82e3
Bug: 78137932
Test: manually run systrace.py against unit tests
Test: manually run systrace.py against benchmarking app
(cherry picked from commit e9e637ab73b68b5982281a3f7c621f6a75d51743)

common/operations/LSTM.cpp

diff --git a/common/operations/LSTM.cpp b/common/operations/LSTM.cpp
index 80b0eb9..7667c66 100644
--- a/common/operations/LSTM.cpp
+++ b/common/operations/LSTM.cpp
@@ -19,6 +19,8 @@
 #include "CpuExecutor.h"
 #include "HalInterfaces.h"
 
+#include "Tracing.h"
+
 namespace android {
 namespace nn {
 
@@ -300,6 +302,8 @@
 }
 
 bool LSTMCell::Eval() {
+  NNTRACE_COMP("LSTMCell::Eval");
+
   const uint32_t n_batch = input_->shape().dimensions[0];
   const uint32_t n_input = input_->shape().dimensions[1];
   // n_cell and n_output will be the same size when there is no projection.