Added Variables to Dockerfile

Dockerfile

@@ -8,12 +8,20 @@ WORKDIR /build
 # Misc -> findutils make git
 # musl-dev is required for the multi lang firmwares
 # clang is required for clang-format (for dev)
+ARG APK_COMPS="gcc-riscv-none-elf gcc-arm-none-eabi newlib-riscv-none-elf \
+               newlib-arm-none-eabi"
+ARG APK_PYTHON="python3 py3-pip black"
+ARG APK_MISC="findutils make git"
+ARG APK_DEV="musl-dev clang bash clang-extra-tools"
 
-RUN apk add --no-cache gcc-riscv-none-elf gcc-arm-none-eabi newlib-riscv-none-elf newlib-arm-none-eabi findutils python3 py3-pip black make git musl-dev clang bash clang-extra-tools
+# PIP packages
+ARG PIP_PKGS='bdflib'
+
+RUN apk add --no-cache ${APK_COMPS} ${APK_PYTHON} ${APK_MISC} ${APK_DEV}
 
 # Install Python3 packages
 
-RUN python3 -m pip install bdflib
+RUN python3 -m pip install ${PIP_PKGS}
 # Git trust
 RUN git config --global --add safe.directory /build/source