ci/docker: add Raspberry Pi picotool and fix GN build

- Add prebuilt Raspberry Pi picotool

- fix GN build with:
     git checkout 5d0a4153b0bcc86c5a23310d5b648a587be3c56d

Signed-off-by: simbit18 <simbit18@gmail.com>

tools/ci/docker/linux/Dockerfile

@@ -43,7 +43,8 @@ RUN apt-get update -qq && DEBIAN_FRONTEND="noninteractive" apt-get install -y -q
   nodejs \
   npm \
   unzip \
-  zip
+  zip \
+  python3
 
 RUN mkdir -p /tools
 WORKDIR /tools
@@ -67,8 +68,10 @@ RUN cd nuttx-tools/kconfig-frontends \
 RUN mkdir -p /tools/gn \
   && cd /tools/gn \
   && git clone https://gn.googlesource.com/gn gn \
-  && cd gn && ./build/gen.py \
-  && cd out && ninja
+  && cd gn \
+  && git checkout 5d0a4153b0bcc86c5a23310d5b648a587be3c56d \
+  && python3 build/gen.py \
+  && ninja -C out
 
 # Upgrade nodejs to the stable version we need before install zap
 RUN npm install -g n && n 20.10.0 node && hash -r
@@ -302,6 +305,15 @@ RUN mkdir -p pico-sdk && \
   curl -s -L "https://github.com/raspberrypi/pico-sdk/releases/download/2.2.0/pico-sdk-2.2.0.tar.gz" \
   | tar -C pico-sdk --strip-components 1 -xz
 
+###############################################################################
+# Build image for tool required by Raspberry Pi picotool builds
+###############################################################################
+FROM nuttx-toolchain-base AS nuttx-toolchain-raspberrypi-picotool
+# Download the prebuilt Raspberry Pi picotool
+RUN mkdir -p picotool && \
+  curl -s -L "https://github.com/raspberrypi/pico-sdk-tools/releases/download/v2.2.0-0/picotool-2.2.0-x86_64-lin.tar.gz" \
+  | tar -C picotool --strip-components 1 -xz
+
 ###############################################################################
 # Final Docker image used for running CI system.  This includes all toolchains
 # supported by the CI system.
@@ -493,6 +505,10 @@ COPY --from=nuttx-toolchain-esp32 /tools/blobs/* /tools/blobs/esp-bins/
 COPY --from=nuttx-toolchain-raspberrypi-pico-sdk /tools/pico-sdk/ pico-sdk/
 ENV PICO_SDK_PATH="/tools/pico-sdk"
 
+# Raspberry Pi picotool
+COPY --from=nuttx-toolchain-raspberrypi-picotool /tools/picotool/ picotool/
+ENV PATH="/tools/picotool:$PATH"
+
 # gn tool
 RUN mkdir -p /tools/gn
 COPY --from=nuttx-tools /tools/gn/gn/out/gn /tools/gn