flash: support both qcom-ptool script layouts in gen-flash-dirs.sh

[Bjordis Collaku (bjordiscollaku)]

Problem

qcom-ptool moved gen_partition.py, ptool.py, and gen_contents.py from the repo root into a qcom_ptool/ package directory (upstream commit f0f1259), and ptool.py now imports its sibling utils module as qcom_ptool.utils.

Every qcom-ptool commit that adds shikra-evk support lands after this restructure. As a result, pinning gen-flash-dirs.sh's --ptool-dir to any commit with shikra-evk support fails with:

python3: can't open file '.../boot_bins/qcom-ptool/gen_partition.py': No such file or directory

This was reported against qcom-distro-images' local developer build guide, which pins an older qcom-ptool commit specifically to avoid this breakage, at the cost of missing shikra-evk support.

Fix

Detect which layout the pinned qcom-ptool checkout uses and resolve the scripts directory (and PYTHONPATH, needed by the new ptool.py intra-package import) accordingly. platforms/ stays at the repo root in both layouts, so no other path resolution changes are needed.

I considered switching to the new pip install . + qcom-ptool unified CLI entry point (which is the direction upstream has moved, and what their own Makefile now uses), but the pkg-builder container has neither pip nor setuptools installed, so that would add a new dependency to the build environment. The layout-detection approach avoids that entirely and keeps gen-flash-dirs.sh self-contained.

Validation

Ran gen-flash-dirs.sh locally against all four resolute/iot boards (iq-x7181-evk, qcs6490-rb3gen2-vision-kit, iq-9075-evk, iq-8275-evk) with:

• The previously pinned qcom-ptool commit (old, repo-root layout): completes successfully, no regression.
• Current qcom-ptool tip (new, qcom_ptool/ layout, includes shikra-evk): completes successfully. Directory structure matches the old-layout run exactly (only additional GPT backup files present, from unrelated upstream ptool changes, not from this fix).
• shikra-evk's own partition config directly: gen_partition.py and ptool.py both run successfully and produce partition XML/GPT output for shikra-evk, confirming the exact failure mode reported is resolved.

Files changed

File	Change
flash/gen-flash-dirs.sh	Detect qcom-ptool script layout (repo root vs qcom_ptool/) and resolve script paths and PYTHONPATH accordingly