Add support for Linux aarch64 builds

images/base-linuxarm64/gen-implib.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+set -e
+if [[ $# != 2 ]]; then
+    echo "Invalid arguments"
+    exit 1
+fi
+IN="$1"
+OUT="$2"
+
+TMPDIR="$(mktemp -d)"
+trap "rm -rf '$TMPDIR'" EXIT
+cd "$TMPDIR"
+
+set -x
+python3 /opt/implib/implib-gen.py --target aarch64-linux-gnu --dlopen --lazy-load --verbose "$IN"
+${FFBUILD_CROSS_PREFIX}gcc $CFLAGS $STAGE_CFLAGS -DIMPLIB_HIDDEN_SHIMS -c *.tramp.S *.init.c
+${FFBUILD_CROSS_PREFIX}ar -rcs "$OUT" *.tramp.o *.init.o