Improve the qcomm aot part docs (#5939)

Improve the qcomm aot part docs (#5868)

Summary:
Pull Request resolved: #5868

the schema file copy is an actual AOT step. It's a workaround but it has been here a while, probably easier to have it as part of the build script instead of manually doing it everytime

Reviewed By: kirklandsign

Differential Revision: D63878765

fbshipit-source-id: 7fc4b848b72e2859364e21cbea3dd1b433d6cd8e
(cherry picked from commit 478a9b6)

Co-authored-by: Chen Lai <[email protected]>

Author: pytorchbot

backends/qualcomm/scripts/build.sh

@@ -135,6 +135,8 @@ if [ "$BUILD_X86_64" = true ]; then
 
     rm -f $PRJ_ROOT/backends/qualcomm/python/*
     cp -fv $BUILD_ROOT/backends/qualcomm/Py* "$PRJ_ROOT/backends/qualcomm/python"
+    cp -fv "$PRJ_ROOT/schema/program.fbs" "$PRJ_ROOT/exir/_serialize/program.fbs"
+    cp -fv "$PRJ_ROOT/schema/scalar_type.fbs" "$PRJ_ROOT/exir/_serialize/scalar_type.fbs"
 
    EXAMPLE_ROOT=examples/qualcomm
    CMAKE_PREFIX_PATH="${BUILD_ROOT}/lib/cmake/ExecuTorch;${BUILD_ROOT}/third-party/gflags;"

docs/source/build-run-qualcomm-ai-engine-direct-backend.md

@@ -147,6 +147,10 @@ cmake --build $PWD --target "PyQnnManagerAdaptor" "PyQnnWrapperAdaptor" -j$(npro
 # The filename might vary depending on your Python and host version.
 cp -f backends/qualcomm/PyQnnManagerAdaptor.cpython-310-x86_64-linux-gnu.so $EXECUTORCH_ROOT/backends/qualcomm/python
 cp -f backends/qualcomm/PyQnnWrapperAdaptor.cpython-310-x86_64-linux-gnu.so $EXECUTORCH_ROOT/backends/qualcomm/python
+
+# Workaround for fbs files in exir/_serialize
+cp $EXECUTORCH_ROOT/schema/program.fbs $EXECUTORCH_ROOT/exir/_serialize/program.fbs
+cp $EXECUTORCH_ROOT/schema/scalar_type.fbs $EXECUTORCH_ROOT/exir/_serialize/scalar_type.fbs
 ```
 
 ### Runtime:
@@ -205,9 +209,6 @@ We use deeplab-v3-resnet101 as an example in this tutorial. Run below commands t
 
 ```bash
 cd $EXECUTORCH_ROOT
-# Workaround for fbs files in exir/_serialize
-cp schema/program.fbs exir/_serialize/program.fbs
-cp schema/scalar_type.fbs exir/_serialize/scalar_type.fbs
 
 python -m examples.qualcomm.scripts.deeplab_v3 -b build-android -m SM8550 --compile_only --download
 ```