tests/docker: update and flatten debian-toolchain

Update to the latest stable Debian. While we are at it flatten into a
single dockerfile as we do not need anything from the base image to
build the toolchain. This is used to build both the nios and
microblaze toolchains.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220914155950.804707-29-alex.bennee@linaro.org>

tests/docker/Makefile.include

@@ -127,10 +127,6 @@ docker-image-debian-nios2-cross: $(DOCKER_FILES_DIR)/debian-toolchain.docker \
     $(DOCKER_FILES_DIR)/debian-nios2-cross.d/build-toolchain.sh
 	$(call debian-toolchain, $@)
 
-# Specialist build images, sometimes very limited tools
-docker-image-debian-microblaze-cross: docker-image-debian10
-docker-image-debian-nios2-cross: docker-image-debian10
-
 # These images may be good enough for building tests but not for test builds
 DOCKER_PARTIAL_IMAGES += debian-alpha-cross
 DOCKER_PARTIAL_IMAGES += debian-powerpc-test-cross

tests/docker/dockerfiles/debian-toolchain.docker

@@ -4,7 +4,7 @@
 # This dockerfile is used for building a cross-compiler toolchain.
 # The script for building the toolchain is supplied via extra-files.
 #
-FROM qemu/debian10
+FROM docker.io/library/debian:11-slim
 
 # Install build utilities for building gcc and glibc.
 # ??? The build-dep isn't working, missing a number of
@@ -15,6 +15,7 @@ RUN apt update && \
     DEBIAN_FRONTEND=noninteractive eatmydata \
     apt install -y --no-install-recommends \
         bison \
+        ca-certificates \
         flex \
         gawk \
         libmpc-dev \
@@ -32,5 +33,5 @@ RUN cd /root && ./build-toolchain.sh
 # Throw away the extra toolchain build deps, the downloaded source,
 # and the build trees by restoring the original debian10 image,
 # then copying the built toolchain from stage 0.
-FROM qemu/debian10
+FROM docker.io/library/debian:bullseye-slim
 COPY --from=0 /usr/local /usr/local