Add libsnappy for hap encoding support

Closes #443

scripts.d/50-snappy.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+
+SCRIPT_REPO="https://github.com/google/snappy.git"
+SCRIPT_COMMIT="32ded457c0b1fe78ceb8397632c416568d6714a0"
+
+ffbuild_enabled() {
+    return 0
+}
+
+ffbuild_dockerbuild() {
+    mkdir build && cd build
+
+    cmake -DCMAKE_TOOLCHAIN_FILE="$FFBUILD_CMAKE_TOOLCHAIN" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX="$FFBUILD_PREFIX" \
+        -DBUILD_SHARED_LIBS=OFF -DSNAPPY_BUILD_TESTS=OFF -DSNAPPY_BUILD_BENCHMARKS=OFF -DSNAPPY_FUZZING_BUILD=OFF \
+        -DSNAPPY_REQUIRE_AVX=OFF -DSNAPPY_REQUIRE_AVX2=OFF ..
+    make -j$(nproc)
+    make install
+}
+
+ffbuild_configure() {
+    echo --enable-libsnappy
+}
+
+ffbuild_unconfigure() {
+    echo --disable-libsnappy
+}