tests/tcg: enable building for RISCV64

As before, using Debian SID compilers.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>

tests/docker/Makefile.include

@@ -76,6 +76,7 @@ docker-image-debian-m68k-cross: docker-image-debian-sid
 docker-image-debian-sh4-cross: docker-image-debian-sid
 docker-image-debian-sparc64-cross: docker-image-debian-sid
 docker-image-debian-mips64-cross: docker-image-debian-sid
+docker-image-debian-riscv64-cross: docker-image-debian-sid
 docker-image-travis: NOUSER=1
 
 # Specialist build images, sometimes very limited tools

tests/docker/dockerfiles/debian-riscv64-cross.docker

+#
+# Docker cross-compiler target
+#
+# This docker target builds on the debian sid base image which
+# contains cross compilers for Debian "ports" targets.
+#
+FROM qemu:debian-sid
+
+RUN DEBIAN_FRONTEND=noninteractive eatmydata \
+    apt-get install -y --no-install-recommends \
+        gcc-riscv64-linux-gnu \
+        libc6-dev-riscv64-cross

tests/tcg/riscv/Makefile.include

+#
+# Makefile.include for all RISCV targets
+#
+# Debian only really cares about 64 bit going forward
+#
+
+ifeq ($(TARGET_NAME),riscv64)
+DOCKER_IMAGE=debian-riscv64-cross
+DOCKER_CROSS_COMPILER=riscv64-linux-gnu-gcc
+endif