Update pico-sdk to 2.1.1

Also manually install picotool from source to ensure its version
matches the sdk version (and doesn't have to be rebuilt by each
firmware build). This was necessary to bump pico-sdk to 2.1.1

Author: dihm

docker/Dockerfile

@@ -22,10 +22,23 @@ FROM base AS buildtools
 RUN \
     mkdir -p /pico/ && \
     cd /pico/ && \
-    git clone https://github.com/raspberrypi/pico-sdk.git --branch 2.0.0 && \
+    git clone https://github.com/raspberrypi/pico-sdk.git --branch 2.1.1 && \
     cd pico-sdk/ && \
     git submodule update --init && \
     cd /
 
 # Set the Pico SDK environment variable
 ENV PICO_SDK_PATH=/pico/pico-sdk/
+
+# Install picotool
+# ensure versions of sdk and picotool match
+RUN \
+    git clone https://github.com/raspberrypi/picotool.git --branch 2.1.1 && \
+    cd picotool && \
+    mkdir build && \
+    cd build && \
+    cmake .. && \
+    make -j$(nproc) && \
+    cmake --install . && \
+    cd ../.. && \
+    rm -rf picotool