tools: Remove tini image

All users in ./pkg and ./test have been converted to use
tini from the alpine base image.

Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com>

tools/tini/Dockerfile

@@ -1,19 +0,0 @@
-FROM linuxkit/alpine:c5021a113803f7608e3908014d316c3490183d0b@sha256:4c7a80173c71ca5019dc56f40442b3a8345f141dd46593bd1fe6d130294d07cb AS build
-RUN apk add \
-    cmake \
-    gcc \
-    make \
-    musl-dev \
-    vim
-
-ENV TINI_VERSION=0.13.0
-ADD https://github.com/krallin/tini/archive/v${TINI_VERSION}.tar.gz tini-${TINI_VERSION}.tar.gz
-
-RUN zcat tini-${TINI_VERSION}.tar.gz | tar xvf -
-RUN cd tini-${TINI_VERSION} && cmake . && make && cp -a tini-static /bin/tini
-
-FROM scratch
-ENTRYPOINT []
-CMD []
-WORKDIR /
-COPY --from=build bin/tini bin/tini

tools/tini/Makefile

@@ -1,14 +0,0 @@
-.PHONY: tag push
-default: push
-
-IMAGE=tini
-DEPS=Dockerfile
-
-HASH?=$(shell git ls-tree HEAD -- ../$(notdir $(CURDIR)) | awk '{print $$3}')
-
-tag: $(DEPS)
-	docker build --no-cache --network=none -t linuxkit/$(IMAGE):$(HASH) .
-
-push: tag
-	DOCKER_CONTENT_TRUST=1 docker pull linuxkit/$(IMAGE):$(HASH) || \
-	DOCKER_CONTENT_TRUST=1 docker push linuxkit/$(IMAGE):$(HASH)

tools/tini/README.md

@@ -1,4 +0,0 @@
-[tini](https://github.com/krallin/tini) is a tiny program which can be
-used as a minimal `init` process for container images.
-
-The `linuxkit/tini` image just contains `/bin/tini` and can be used as the base image by packages, requiring `tini`.