add rtlsdr via soapy to the docker builds; clean up

docker/scripts/install-dependencies-rtlsdr-soapy.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+function cmakebuild() {
+  cd $1
+  if [[ ! -z "${2:-}" ]]; then
+    git checkout $2
+  fi
+  mkdir build
+  cd build
+  cmake ..
+  make
+  make install
+  cd ../..
+  rm -rf $1
+}
+
+cd /tmp
+
+STATIC_PACKAGES="libusb"
+BUILD_PACKAGES="git libusb-dev cmake make gcc musl-dev g++ linux-headers"
+
+apk add --no-cache $STATIC_PACKAGES
+apk add --no-cache --virtual .build-deps $BUILD_PACKAGES
+
+git clone https://github.com/osmocom/rtl-sdr.git
+cmakebuild rtl-sdr b5af355b1d833b3c898a61cf1e072b59b0ea3440
+
+git clone https://github.com/pothosware/SoapyRTLSDR.git
+cmakebuild SoapyRTLSDR 5c5d9503337c6d1c34b496dec6f908aab9478b0f
+
+apk del .build-deps